Comparing calcite and phosphate oxygen isotope paleothermometers - d18O of Silurian brachiopods and conodonts - Joachimski, Michael; et al. (Geochimica Et Cosmochimica Acta, 2000)
Oxygen isotope compositions of Silurian calcitic brachiopod shells from Gotland are compared with those of phosphatic inarticulate brachiopod shells and conodonts from identical stratigraphic horizons. The δO(phosphate) values of inarticulate brachiopod shells vary widely (13.0 to 17.5‰ V-SMOW) and are significantly lower than those of coeval conodont samples (17.5 to 19.5‰ V-SMOW). Conodont samples from individual beds have homogenous δO(phosphate) values with variations close to the analytical precision (±0.2‰). Together with a significant correlation of conodont δO(phosphate) and articulate brachiopod shell δO(carbonate) values (r = 0.85), this observation suggests that primary marine oxygen isotope compositions are better preserved in conodont apatite than in inarticulate brachiopod shell apatite. However, with decreasing δO(carbonate) values, the δO(phosphate) values of conodonts are higher than expected for theoretical isotopic equilibrium with brachiopod calcite. Different habitats of conodonts and brachiopods cannot account for the observed offset in δO because both organisms were thriving on a broad shallow marine carbonate platform. Whereas δO(phosphate) values of Silurian conodonts are close to δO(phosphate) values of modern and Mesozoic tropical biogenic apatites, most Silurian calcitic brachiopod shells from Gotland are depleted in O when compared to modern or Mesozoic brachiopods. We therefore suggest that Silurian conodonts from Gotland record paleotemperature and δO of Silurian sea water more faithfully than coeval calcitic brachiopod shells. Copyright (C) 2000 Elsevier Science Ltd.
UnivIS-Import:2015-03-09:Pub.2000.nat.dgeo.IGM.LG.compar

Comparing oxygen isotope records of Silurian calcite and phosphate-δ18O compositions of brachiopods and conodonts - Joachimski, Michael; et al. (Geochimica Et Cosmochimica Acta, 2000)
Oxygen isotope compositions of Silurian calcitic brachiopod shells from Gotland are compared with those of phosphatic inarticulate brachiopod shells and conodonts from identical stratigraphic horizons. The δO(phosphate) values of inarticulate brachiopod shells vary widely (13.0 to 17.5‰ V-SMOW) and are significantly lower than those of coeval conodont samples (17.5 to 19.5‰ V-SMOW). Conodont samples from individual beds have homogenous δO(phosphate) values with variations close to the analytical precision (±0.2‰). Together with a significant correlation of conodont δO(phosphate) and articulate brachiopod shell δO(carbonate) values (r = 0.85), this observation suggests that primary marine oxygen isotope compositions are better preserved in conodont apatite than in inarticulate brachiopod shell apatite. However, with decreasing δO(carbonate) values, the δO(phosphate) values of conodonts are higher than expected for theoretical isotopic equilibrium with brachiopod calcite. Different habitats of conodonts and brachiopods cannot account for the observed offset in δO because both organisms were thriving on a broad shallow marine carbonate platform. Whereas δO(phosphate) values of Silurian conodonts are close to δO(phosphate) values of modern and Mesozoic tropical biogenic apatites, most Silurian calcitic brachiopod shells from Gotland are depleted in O when compared to modern or Mesozoic brachiopods. We therefore suggest that Silurian conodonts from Gotland record paleotemperature and δO of Silurian sea water more faithfully than coeval calcitic brachiopod shells. Copyright (C) 2000 Elsevier Science Ltd.

Comparing Phase Development and Rheological Properties of OPC Paste Within the First Hour of Hydration - Jakob, Cordula; Jansen, Daniel; Pott, Ursula; Neubauer, Jürgen (Rheology and Processing of Construction Materials, 2020)
In this paper the very early hydration of ordinary Portland cement at 20 °C and 30 °C is investigated, focussing on the first hour after the addition of water. The development of the rheological behaviour of cement paste during hydration is compared with the kinetics determined by quantitative in-situ X-ray diffraction (QXRD) and heat flow calorimetry. For both temperatures the cumulative heat correlates very well with the evolution of ettringite content over the first hour of hydration. The precipitation rate of ettringite is strongly influenced by temperature. This results in a higher formation rate of ettringite already in the first minutes after mixing at 30 °C. Analogously the temperature affects the rheological behaviour of the cement paste. The measured torque values are also higher for 30 °C from the first point of investigation on. Furthermore, the increasing torque can be linked to the rise in the ettringite content at both temperatures. The formation of other hydrate phases influencing the development of the rheological behaviour within the observed time frame cannot be proven with the data at hand. Therefore, it can be assumed that ettringite content is the determining mineral for the early workability of cement pastes.
CRIS-Team Scopus Importer:2019-10-22
Keywords: Ettringite formation; Hydration kinetics; OPC; Rheology; Temperature

Comparing the nature of the western and eastern Azores mantle - Genske, Felix S.; Beier, Christoph; Stracke, Andreas; Turner, Simon P.; Pearson, Norman J.; Hauff, Folkmar; Schaefer, Bruce F.; Haase, Karsten (Geochimica Et Cosmochimica Acta, 2016)
The Azores islands in the central North-Atlantic originate from a regional melting anomaly, probably created by melting hot, unusually hydrous and geochemically enriched mantle. Here, we present Hf, Pb and Os isotopic data in geochemically well-characterised primitive lavas from the islands Flores and Corvo that are located west of the Mid-Atlantic Ridge (MAR), as well as submarine samples from a subsided island west of Flores and from Deep Sea Drilling Project (DSDP) holes drilled in the western part of the Azores platform and beyond. These are compared to existing data from the Azores islands east of the MAR. The geodynamic origin of the two islands west of the ridge axis and furthest from the inferred plume centre in the central part of the plateau is enigmatic. The new data constrain the source compositions of the Flores and Corvo lavas and show that the western and eastern Azores mantle is isotopically similar, with the exception of an enriched component found exclusively on eastern São Miguel. Trace element ratios involving high field strength elements (HFSE) are distinctly different in the western islands (e.g. twofold higher Nb/Zr) compared to any of the islands east of the MAR. A similar signature is observed in MAR basalts to the south of the Azores platform and inferred to originate from (auto-) metasomatic enrichment of the sub-ridge mantle (Gale et al., 2011, 2013). In a similar fashion, low degree melts from an enriched source component may metasomatise the ambient plume mantle underneath the western Azores islands. Melting such a modified plume mantle can explain the chemical differences between lavas from the western and eastern Azores islands without the need for additional plume components. Recent re-enrichment and intra melting column modification of the upwelling mantle can cause local to regional scale geochemical differences in mantle-derived melts.

Comparison between Measured and Calculated Thermal Conductivities within Different Grain Size Classes and Their Related Depth Ranges - Bertermann, David; Müller, Johannes; Freitag, Simon; Schwarz, Hans (Soil Systems, 2018)
In the field of the efficiency of very shallow geothermal energy systems, there is still a significant need for research activity. To ensure the proper exploitation of this energy resource, the decisive geophysical parameters of soil must be well-known. Within this study, thermal conductivity, as a fundamental property for evaluating the geothermal potential of very shallow geothermal systems, was analyzed and measured with a TK04 device. A dataset, consisting of various geophysical parameters (thermal conductivity, bulk density, water content, and porosity) determined for a large range of different textural soil classes, was collated. In a new approach, the geophysical properties were visualized covering the complete grain size range. The comparison between the measured and calculated thermal conductivity values enabled an investigation with respect to the validity of the different Kersten equations. In the course of this comparison, the influence of effective bulk density was taken into account. In conclusion, both Kersten formulas should be used as recommended and regular bulk density corresponded better to the reference dataset representing the outcomes of the TK04 laboratory measurement. Another objective was to visualize the relation of thermal conductivities within their corresponding textural classes and the validity of Kersten formulas for various bulk densities, depths, and soils. As a result, the accessibility to information for expedient recommendations about the feasibility of very shallow geothermal systems will be improved. Easy, accessible know-how of the fundamentals is important for a growing renewable energy sector where very shallow geothermal installations can also cover heating and cooling demands.
Keywords: soil properties; thermal conductivity; bulk density; textural soil classes; TK04 measurements

Comparison of ground temperature response of energy pile and borehole heat exchanger during thermal response tests - Luo, Jin; Zhao, Haifeng; Gui, Shuqiqang; Xiang, Wei; Rohn, Joachim (Environmental Earth Sciences, 2016)
Thermal migration of ground heat exchanger (GHE) in subsurface is crucially important to the efficiency and sustainability of ground source heat pump systems. In order to investigate heat transfer efficiency of GHE, ground temperature response during system operation should be analyzed. In this paper, two types of GHEs operate under heating operating condition are simulated by thermal response test. A set of parameters including fluid temperature, borehole wall and ground temperature are monitored with duration of 148 h. The analysis of thermal performance shows that the energy pile has specific thermal rates of 147 W/m which is 230% higher than that of borehole heat exchanger with 56 W/m. Furthermore, heat flux per unit area of the contacting area at borehole wall (q¯ , W/m2) is analyzed. The monitored temperature development at the borehole wall for both types of GHEs can be perfectly explained by q¯. The finding of this study indicates that the parameter is useful in estimating ground thermal accumulation of GHEs. The larger the q¯ is, the higher the possible of ground thermal accumulation and unstable performance of GHEs would be. © 2016, Springer-Verlag Berlin Heidelberg.
Keywords: Boreholes; Geothermal heat pumps; Heat exchangers; Heat flux; Heat pump systems; Heat transfer; Borehole heat exchangers; Energy piles; Ground heat exchangers; Ground temperature; Heat transfer efficiency; Temperature development; Thermal accumulation; Thermal response test; Piles

Comparison of Measured and Derived Thermal Conductivities in the Unsaturated Soil Zone of a Large-Scale Geothermal Collector System (LSC) - Rammler, Mario; Schwarz, Hans; Wagner, Jan; Bertermann, David (Energies, 2023)
The design, energetic performance, and thermal impact of large-scale geothermal collector systems (LSCs) are dependent on the thermal conductivity of unsaturated soils (λ). The aim of this study was to investigate the benefits of two different λ measurement methods using single-needle sensor measuring devices on a laboratory scale. Since large-scale determinations are required in the context of LSCs, the potential for deriving λ from electrical resistivity tomography measurements (ERTs) was also examined. Using two approaches—the continuous evaporation method and the punctual method—thermal conductivities of soil samples from Bad Nauheim (Germany) were measured. The results were compared with averaged λ derived from three ERT sections. With the evaporation method, significant bulk density changes were observed during the experimental procedure, which were caused by the clay content and the use of repacked samples. The punctual method ensures a sufficiently constant bulk density during the measurements, but only provides a small number of measurement points. The thermal conductivities derived from ERTs show largely minor deviations from the laboratory measurements on average. If further research confirms the results of this study, ERTs could provide a non-invasive and unelaborate thermal exploration of the subsurface in the context of large-scale infrastructure projects such as LSCs.<br
Keywords: large-scale geothermal collector system (LSC); thermal conductivity of soils; single-needle sensor; electrical resistivity tomography (ERT); shrinkage of soils; unsaturated soil zone

Comparison of organic and inorganic carbon isotope patterns across the Frasnian/Famennian boundary. - Joachimski, Michael (Palaeogeography, Palaeoclimatology, Palaeoecology, 1997)
The carbon isotopic composition of organic matter is reported for two Frasnian-Famennian boundary sections from the Rheinische Schiefergebirge (Germany). During the late Frasnian δ13C(org) values commonly range from -27.5‰ to -26‰. Highest δ13C(org) values around -24‰ are encountered immediately above and below the Kellwasser horizons. All samples from the Kellwasser horizons are depleted in δ13C(org) by -2.5‰ to -4.7‰. This depletion is explained by a higher proportion of biomass derived from isotopically depleted chemoautotrophic bacteria. A comparison of the positive δ13C excursions shows that the δ13C(org) shifts precede the 13C(carb) shifts by some 105 years. Consequently, Δδ13C values document a shift towards lower values below the Upper Kellwasser horizon. A contribution of terrestrial organic matter, as well as a thermal alteration of the δ13C(org) signals, do not provide compelling explanations for the earlier δ13C(org) shift. Increases in primary productivity or carbon burial rate will change the CO2(aq) content of surface waters, affect the carbon isotope fractionation during photosynthetic carbon uptake and thus enrich organic carbon in 13C. However, both processes cannot account for the earlier onset of the δ13C(org) shift, because the δ13C(carb) record should document the resulting 13C enrichment in surface waters as well. A reduction in the calcium carbonate precipitation rate, due to the global extinction of the reef ecosystem, may have played an important role in reducing the CO2(aq) content of surface waters without changing the isotopic composition of surface waters. Whether this process or other factors, such as a rise in sea-surface temperature or a change in the phytoplankton association, account for the earlier onset of the positive shift in the δ13C(org) curve must be determined by further studies that may be able to confirm the global significance of the reported δ13C(org) pattern in Frasnian-Famennian boundary sections from other parts of the globe.
UnivIS-Import:2015-03-05:Pub.1997.nat.dgeo.IGM.LG.compar
Keywords: Carbon; Frasnian-Famennian; Germany; Isotopes; Organic carbon; Rheinisches Schiefergebirge (Rhenish Slate Mountains); Upper Devonian

Comparison of physical and physicochemical methods for 3D printing application with the focus on the unconfined uniaxial compression test - Pott, Ursula; Jakob, Cordula; Wolf, Julian; Stephan, Dietmar (Construction and Building Materials, 2023)
For a commercial success of 3D concrete printing, standardisation is necessary to enable industrial production. To select methods for standardisation from the material side, detailed knowledge of suitable methods and of material behaviour is required in advance. Therefore, this study aims to compare different methods for investigating stiff printable mortars during the transition regime of a non-Newtonian fluid to a cohesive frictional material by physical and physicochemical methods focusing on the unconfined uniaxial compression test. The study shows that all methods exhibit comparable progressions, although the results are affected differently by self-heating, material composition and progressive hydration.
CRIS-Team Scopus Importer:2023-07-21
Keywords: Apparent static and dynamic Young's modulus; Early age mortar properties; Green strength; In-situ QXRD; Isothermal heat flow calorimetry; Slow penetrating sphere test; Ultrasonic wave transmission test

Comparison of precipitation collectors used in isotope hydrology - Michelsen, Nils; van Geldern, Robert; Roßmann, Y; Bauer, I; Schulz, S; Barth, Johannes; Schüth, Christoph (Chemical Geology (Isotopic Geoscience) Section, 2018)
Many hydrologic studies require data on the oxygen and hydrogen stable isotope composition (δ18O, δ precipitation and various collector designs have been suggested for gathering corresponding samples. Yet, crucial that these collectors, also known as totalizers, prevent evaporation and associated isotope fractionation. Surprisingly, we were unable to find a comprehensive collector intercomparison in the literature, and much one that addressed hot and arid conditions. In this study, we tested six different collector designs over a period of 32 days. They were filled to 20% total volume with water of known isotope composition and placed in a modified laboratory drying oven low relative humidity (5%) and a diurnal temperature change of 26 to 45 °C. Evaporative mass losses determined gravimetrically daily while samples for isotope analyses were collected every four days. The classic Oil collector, featuring a layer of paraffin oil to prevent evaporation, showed the smallest losses and no detectable isotope shift. The Tube-dip-in-water collector with pressure equilibration tube performed well, although we noted somewhat larger mass losses and isotope shifts. The latter accounted 0.28‰(Δδ18O) and 0.9‰(Δδ2 H) after 32 days, which is significant, but in view of the extreme conditions, changes should be still acceptable for most studies. The remaining collectors (Ball-in-funnel, Floating balls, Float based) all failed. Under the prevailing conditions, the Tube-dip-in-water collector with pressure equilibration tube seems represent a good, oil- and thus contamination-free compromise. Nonetheless, also in this system small cipitation amounts are problematic. This may necessitate modifications of the standard design in terms of diameter and bottle geometry. We strongly advise researchers to conduct own tests with their intended collector before field deploymen
Keywords: stable isotopes; rain water; sampler design

Comparison of whole wood and cellulose carbon and oxygen isotope series from Pinus nigra ssp. laricio (Corsica/France). - Szymczak, Sonja; Joachimski, Michael; Bräuning, Achim; Hetzer, Timo; Kuhlemann, Joachim (Dendrochronologia, 2011)
Stable isotopes in tree rings have widely been used for palaeoclimate reconstructions since tree rings record climatic information at annual resolution. However, various wood components or different parts of an annual tree-ring may differ in their isotopic compositions. Thus, sample preparation and subsequent laboratory analysis are crucial for the isotopic signal retained in the final tree-ring isotope series used for climate reconstruction and must therefore be considered for the interpretation of isotope–climate relationships. This study focuses on wood of Corsican Pine trees (Pinus nigra ssp. laricio) as this tree species allows to reconstruct the long-term climate evolution in the western Mediterranean. In a pilot study, we concentrated on methodological issues of sample preparation techniques in order to evaluate isotope records measured on pooled whole tree-ring cellulose and whole tree-ring bulk wood samples. We analysed 80-year long carbon and oxygen chronologies of Corsican Pine trees growing near the upper tree line on Corsica. Carbon and oxygen isotope records of whole tree-ring bulk wood and whole tree-ring cellulose from a pooled sample of 5 trees were correlated with the climate parameters monthly precipitation, temperature and the self-calibrating Palmer Drought Severity Index (sc-PDSI). Results show that the offsets in carbon and oxygen isotopes of bulk wood and cellulose are not constant over time. Both isotopes correlate with climate parameters from late winter and summer. The carbon and oxygen isotope ratios of cellulose are more sensitive to climatic variables than those of bulk wood. The results of this study imply that extraction of cellulose is a pre-requisite for the reconstruction of high-resolution climate records from stable isotope series of P. nigra ssp. laricio.
UnivIS-Import:2015-03-09:Pub.2011.nat.dgeo.IGM.LG.compar
Keywords: Pinus nigra ssp. laricio; Corsica

Compositional variation and 226Ra-230Th model ages of axial lavas from the southern Mid-Atlantic Ridge, 8°48′S - Haase, Karsten; Brandl, Philipp; Devey, Colin; Hauff, Folkmar; Melcher, Bernd; Garbe-Schönberg, Dieter; Kokfelt, Thomas; Paulick, Holger (Geochemistry Geophysics Geosystems, 2016)
We present geological observations and geochemical data for the youngest volcanic features on the slow spreading Mid-Atlantic Ridge at 8°48′S that shows seismic evidence for a thickened crust and excess magma formation. Young lava flows with high sonar reflectivity cover about 14 km in the axial rift and were probably erupted from two axial volcanic ridges each of about 3 km in length. Three different lava units occur along an about 11 km long portion of the ridge, and lavas from the northern axial volcanic ridge differ from those of the southern axial volcanic ridge and surrounding lava flows. Basalts from the axial rift flanks and from a pillow mound within the young flows are more incompatible element depleted than those from the young volcanic field. Lavas from this volcanic area have Ra-Th disequilibria model ages of 1000 and 4000 years whereas the older lavas from the rift flank and the pillow mound, but also some of the lava field, are older than 8000 years. Glasses from the northern and southern ends of the southern lava unit indicate up to 100°C cooler magma temperatures than in the center and increased assimilation of hydrothermally altered material. The compositional heterogeneity on a scale of 3 km suggests small magma batches rising vertically from the mantle to the surface without significant lateral flow and mixing. The observations on the 8°48′S lava field support the model of low-frequency eruptions from single ascending magma batches that has been developed for slow spreading ridges.
Keywords: basalt; mid-ocean ridge; volcanism

Compositional variation of mafic calc-alkaline lavas at the submarine Pausanias Volcanic Field, western South Aegean Volcanic Arc: Implications for magma formation and ascent - Wölki, Dominic; Beier, Christoph; Haase, Karsten; Günther, Thomas (Lithos, 2022)
The calc-alkaline lavas of the submarine Pausanias Volcanic Field and the neighboring Methana peninsula represent the largest volcanic edifices of the western South Aegean Volcanic Arc (SAVA) in the Mediterranean Sea and erupted on 30–35 km thick continental crust. We report the first whole rock major and trace elements together with Sr-Nd-Pb isotope ratios for basaltic to andesitic lavas from the submarine Pausanias Volcanic Field consisting of six smaller, volcanic structures. The mafic lavas have the most primitive compositions of the SAVA with MgO of up to 9 wt% and Ni concentrations >100 ppm. The incompatible trace element abundance patterns of the Pausanias and Methana lavas overlap and have typical island arc patterns, but Pausanias lavas display a larger geochemical heterogeneity on a smaller spatial scale compared to those from Methana. The Pausanias lavas resemble those from Methana in Sr, Nd, and Pb isotopes reflecting higher sediment subduction in the western SAVA than in the central arc at Santorini. The variability of incompatible element concentrations at relatively constant isotope compositions suggests variable degrees of partial melting of a peridotite-sediment mélange diapir in the mantle wedge. The Pausanias magmas formed from a less depleted mantle source compared to the central SAVA and their ascent in an extensional basin supported relatively rapid ascent without the extensive stagnation in the crust observed in the Methana magmas. The compositional differences between Pausanias and Methana imply differences in their composition and/or transport in the mantle wedge and the crust, allowing highly variable melts to reach the surface within a spatial distance of few kilometers.
CRIS-Team Scopus Importer:2022-07-01
Keywords: Aegean Arc; Mediterranean Sea; Olivine; Spinel; Submarine volcanism; Submarine volcano

Compositional zoning in dolomite from lawsonite-bearing eclogite (SW Tianshan, China): Evidence for prograde metamorphism during subduction of oceanic crust. - Li, Jilei; Klemd, Reiner; Gao, Jun; Meyer, Melanie (American Mineralogist, 2014)
Dolomite with compositional zoning was discovered in carbonate-lawsonite- bearing eclogites in the Tianshan (ultra-)high-pressure/low-temperature metamorphic belt, northwestern China. The eclogite-facies dolomite occurs as matrix porphyroblast and as inclusion in garnet, both of which display the same chemical zoning pattern. The dolomite contains inclusions of calcite (probably after aragonite), magnesite, glaucophane, lawsonite (and its pseudomorphs), allanite, epidote, paragonite, phengite, and omphacite. The chemical zoning in dolomite is well defined by a continuous core-to-rim Mg increase and Fe-Mn decrease. The concentrations of transition metal elements, REE, and Y also decrease from core to rim of the dolomite. Thermodynamic modeling demonstrates that the Fe-Mg zoning of dolomite is largely temperature dependent and, thus, is interpreted as prograde growth zoning, which developed during subduction of carbonate-bearing oceanic crust. It is suggested that dolomite in equilibrium with garnet formed as a result of changing matrix compositions due to increasing temperatures. In addition, thermodynamic modeling demonstrates that during subduction at high-pressure conditions prograde-formed aragonite and dolomite were transformed to dolomite and magnesite. Furthermore, Fe-rich magnesite inclusions in matrix dolomite and in dolomite inclusions in garnet are shown to have formed during high-pressure conditions prior to peak metamorphic conditions and, therefore caution is warranted using Fe-bearing magnesite occurrences in eclogite-facies rocks as an unambiguous ultrahigh pressure indicator as previously suggested. © 1997 - 2014 Mineralogical Society of America. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2014.nat.dgeo.IGM.c3geoc.compos_1
Keywords: Dolomite; Eclogite; High pressure; Magnesite; Prograde zoning; Tianshan

Composition and distinction of white nephrite from Asian deposits - Schmädicke, Esther; et al. (Neues Jahrbuch für Mineralogie-Abhandlungen, 2013)
Keywords: Asian nephrite deposits; Archaeology; Tremolite; Electron microprobe analysis; White nephrite

CONCH - ammonoid morphometric software - Hoffmann, René; Weinkauf, Manuel; Wiedenroth, Kurt; Goeddertz, Peter; de Baets, Kenneth (2019)
Morphological analyses of ammonites are a time-consuming process. The software CONCH allows to gather the established sets of morphological characteristics (i.e., diameter, whorl height, whorl interspace, umbilical width) as well as the traditionally derived parameters and three different rib density parameters in steps of 10, 30 or 45 radial degrees. Data can be exported as .csv files, images of the ammonites with set landmarks can be saved, and projects can be stored for later continuation. The software thus streamlines ammonite analyses and allows scientists to converge on a single software to perform all ammonite morphological analyses for enhanced compatibility in the futur

Concluding IGCP 503: Towards a holistic view of Ordovician and Silurian earth systems - Harper, David A.T.; Li, Jun; Munnecke, Axel; Owen, Alan W.; Servais, Thomas; Sheehan, Peter M. (EPISODES, 2011)
IGCP 503 'Ordovician Palaeogeography and Palaeoclimaté was established in 2004 primarily to identify the main drivers, both biological and geological, of the Great Ordovician Biodiversification Event. From the outset of the project it was clear that this event was part of a larger-scale, long-term, multifaceted process that included the end Ordovician extinction and Silurian recovery, if not more. IGCP 503 thus developed a major network that included scientists whose interests spanned the entire Lower Palaeozoic and encompassed a range of disciplines from classical palaeontology and palaeoecology through isotope geochemistry to climate modellin
Keywords: Ordovician; palaeogeography; palaeoclimate; GOBE; great ordovician biodiversification event; IGCP; Silurian recovery; Ordovician event; lower palaeozoic

Concurrent kinetics of crystallization and toughening in multicomponent biomedical SiO2-Li2O-P2O5-ZrO2 glass-ceramics - Lubauer, Julia; Belli, Renan; Petschelt, Anselm; Cicconi, Maria Rita; Hurle, Katrin; Lohbauer, Ulrich (Journal of Non-Crystalline Solids, 2021)
We investigate here the crystallization kinetics of two pre-crystallized multicomponent dental glass-ceramics (IPS e.max® CAD, Ivoclar-Vivadent; Suprinity® PC, Vita Zahnfabrik) by interrupting the heat treatment at different periods of the non-isothermal and isothermal stage at 840°C. Differential scanning calorimetry (DSC) was used to characterize the crystallization peaks of the pre-crystallized and the base glass, and dilatometry was used to determine the coefficient of thermal expansion and Tg after different times at the maximum temperature. The evolution of crystallinity was tracked by XRD, while the evolution of fracture toughness was obtained by the ball-on-three-balls surface crack in flexure method. The change in microstructural features was made visible using FE-SEM. We show that the isothermal stage is dominated by the transformation of Li2SiO3 in Li2Si2O5, inducing the impingement of nanocrystals into clusters. The residual glass became thereby less polymerized. The kinetics of toughening followed closely the evolution of crystallinity in both systems.
CRIS-Team Scopus Importer:2021-02-12

Conditions of melting beneath the Azores - Beier, Christoph; Haase, Karsten; Turner, Simon P. (Lithos, 2012)
The depth and temperatures of melting beneath Ocean Islands provide important constraints on mantle melting dynamics. The central Azores islands of Faial, Pico, Graciosa and São Jorge are ideally suited for calculating depth and temperatures of melting because they are situated orthogonal to the slow spreading Mid-Atlantic Ridge and thus supposedly on variable lithosphere thicknesses which allow to constrain on the influence of lithosphere thickness on average melting depth. The dataset presented here is used to test the spatial pattern of potential temperature anomalies in the Azores mantle plume. Trace elements indicate comparable degrees of partial melting for all three islands, while Sr-Nd-Pb isotope ratios and incompatible trace element ratios imply only small-scale source heterogeneity that is not related to the major element systematics. Thus, the observed differences in calculated, primary SiO , FeO and TiO (and Al O ) are inferred to reflect changes in melting pressures and temperatures that are independent of source composition. Melting temperatures in the Azores are lower and melting starts deeper than at other mantle plumes (e.g., Hawaii). This implies that the smaller size of the Azores compared to other mantle plumes might be the result of a much smaller anomaly with a large variability of depths and temperatures of melting even on the scale of an individual island. This small-scale variability is of importance when comparing pressures and temperatures between different islands or even globally. The Azores lavas have temperatures lower than predicted for a dry mantle solidus indicating the presence of at least 200ppm H O in the Azores mantle source. © 2012 Elsevier B.V.
Keywords: Azores; Geodynamics; Major elements; Ocean Island Basalts; P-T estimates

Cone morphologies associated with shallow marine eruptions: East Pico Island, Azores - Mitchell, Neil C.; Stretch, Rachelle; Oppenheimer, Clive; Kay, Daniel; Beier, Christoph (Bulletin of Volcanology, 2012)
Eruptions in shallow water typically produce cones of volcaniclastic material. In order to identify any systematic effects of water depth and other environmental parameters on cone morphology, we have measured the heights and widths of cones in multibeam echo-sounder data from a submarine ridge extending southeast from Pico Island, Azores. XRF analyses of dredged samples show that lavas here vary compositionally from alkali basalt to trachybasalt and trachyandesite. Cones in deeper water are generally steep-sided with upper flanks close to 30°, the dip of talus at the angle of repose. However, height/width ratios of cones vary more in shallow water (200-400-m summit depth) with extreme values below 0. 1; while some shallow-water cones are steep-sided as in deep water, others are much flatter. Three such cones lie on a bench at 300-m depth immediately east of Pico Island and have flank slopes of only 10-20°. We speculate that exceptionally shallow cone slopes here were produced by forced spreading of the erupting columns on reaching the water-air density barrier. © 2012 Springer-Verlag Berlin Heidelberg.
Keywords: Cone morphologies; Pico Island; Shallow marine eruptions; Volcaniclastic material

Conodont and carbon isotope stratigraphy near the Frasnian/Famennian (Devonian) boundary at Wulankeshun, Junggar Basin, NW China - Wang, Z. H.; Becker, R. T.; Aboussalam, Z. S.; Hartenfels, S.; Joachimski, Michael; Gong, Y. M. (Palaeogeography, Palaeoclimatology, Palaeoecology, 2016)
Conodont faunas from the Wulankeshun section in the northwestern Junggar Basin of Xinjiang, NW China, are characterized by shallow-water assemblages with many endemic taxa. This study presents separate local icriodid and polygnathid conodont zonations for the Lower Member of the Hongguleleng Formation, which can only roughly be correlated with the pelagic "standard zonation". The basal beds of the Hongguleleng Formation are assigned to a low diverse Icriodus praealternatus ferus n. ssp. Zone, which possibly includes latest Frasnian strata but it continues into the basal Famennian. At present, the Frasnian/Famennian boundary cannot be defined unequivocally by conodonts and there are no obvious Upper Kellwasser equivalents. However, the carbon isotope data are comparable with the Bulongguor Reservoir stratotype, where the top-Frasnian lies within the basal Hongguleleng Formation. In the early Famennian, partly endemic icriodid lineages provide successive Icriodus cornutus, I. stenoancylus junggarensis n. ssp., and I. plurinodosus n. sp. (sub)zones. The basal Famennian is possibly marked by the oldest, endemic species of Neopolygnathus, Neo. huijunae n. sp. It is followed by local Neo. communis communis, "Polygnathus" pomeranicus, Po. cf. szulczewskii, and "Po." pseudocommunis n. sp. zones. The new local conodont zonations provide a high biostratigraphic resolution for further future studies. The Wulankeshun shallow-water conodont faunas show restricted similarities with contemporaneous faunas from eastern Europe, Kazakhstan, and Iran. There are a few taxa that were originally described from other distant regions, such as NW Canada and eastern Australia. The local high number of endemic taxa (17 (sub)species, 46%) points to a significant plate tectonic isolation of the Junggar Basin in the early Famennian.
Keywords: Carbon isotopes; Conodonts; Frasnian/Famennian; Junggar Basin; Late Devonian

Conodont apatite oxygen isotope record of the Permian: ice volume and palaeotemperature evolution - Chen, Bo; Joachimski, Michael; Shen, Shu-Zhong; Lambert, Lance L.; Lai, Xu-Long; Wang, Xiang-Dong; Chen, Jun; Yuan, Dong-Xun (Gondwana Research, 2013)
UnivIS-Import:2015-03-09:Pub.2013.nat.dgeo.IGM.LG.conodo_6

Conodont apatite δ18O signatures indicate climatic cooling as a trigger of the Late Devonian mass extinction - Buggisch, Werner; Joachimski, Michael (Geology, 2002)
UnivIS-Import:2015-03-09:Pub.2002.nat.dgeo.IGM.LG.conodo
Keywords: 18O/16O; Apatite; Late Devonian; Mass extinction; Paleotemperature

Conodont apatite δ18O signatures indicate climatic cooling as a trigger of the Late Devonian mass extinction: Reply - Joachimski, Michael; Buggisch, Werner (Geology, 2003)

Conodont biostratigraphy and carbon isotope stratigraphy of the middle Ordovician (Darriwilian) Komstad Limestone Formation, southern Sweden - Wu, Rongchang; Calner, Mikael; Lehnert, Oliver; Lindskog, Anders; Erlström, Mikael; Joachimski, Michael (GFF, 2018)

Conodont biostratigraphy and carbon isotope stratigraphy of the Middle Ordovician (Darriwilian) Komstad Limestone, southern Sweden - Wu, Rong Chang; Calner, Mikael; Lehnert, Oliver; Lindskog, Anders; Joachimski, Michael (GFF, 2018)
Keywords: carbon isotope stratigraphy; conodont biostratigraphy; Darriwilian; Komstad Limestone; Middle Ordovician; Sweden

Conodont biostratigraphy and palaeoenvironmental trends during the Famennian (Late Devonian) in the thuringian buschteich section (Germany) - Girard, C.; Cornée, J. J.; Charruault, A. L.; Corradini, C.; Weyer, D.; Bartzsch, K.; Joachimski, Michael; Feist, R. (Newsletters on Stratigraphy, 2017)
This study characterizes the stratigraphical context as well as the palaeoenvironmental and sealevel trends during the Late Frasnian and Famennian in the Buschteich section (Thuringia, Germany). An integrated approach combines conodont biostratigraphy, chemostratigraphy based on carbon and oxygen isotopes, conodont biofacies analyses and investigations of the morphotypes of foraminifera that occur in the section was applied. Conodonts provided a fine-scale biostratigraphical framework. All the Famennian conodont biozones were identified, with the exception of the three lowest. The Frasnian-Famennian transition was further identified by a positive carbon isotope excursion. This continuous Famennian record is developed in a condensed limestone succession. The reddish Griotte facies, typical of strata of this period, were not documented. Black shales were not developed except for an interval of dark colored mud rocks corresponding to the Hangenberg event at the top of the section. The carbonate succession of Buschteich was deposited in an outer ramp environment, pelagic organisms are the dominant fauna. This is corroborated by the overall dominance of the deep-water conodont genus Palmatolepis. Microfacies, conodont biofacies and foramini - fera indicated a deepening trend from the Lower crepida to the Lower rhomboidea Zone, followed by a shallowing trend from the Upper rhomboidea to the praesulcata Zone. This sequence overall matches the sea level reference curve for Euramerica. The timing of maximum water depth at Buschteich, as well as the general sea-level reference record, differs from the Col des Tribes (Montagne Noire, France). Differential uplift or overprinting of the long-term eustatic changes may be the cause of the discrepancy in the local sea-level records.
Keywords: Conodonts; Depositional environment; Microfacies; Saxo-thuringian; Sea level; Upper devonian

Conodont biostratigraphy in the Early to Middle Ordovician strata of the Oslobreen Group in Ny Friesland, Svalbard - Lehnert, Oliver; Stouge, Svend; Brandl, Philipp (Zeitschrift der Deutschen Gesellschaft für Geowissenschaften, 2013)
The remotely located Cambro-Ordovician strata in Ny Friesland, NE Spitsbergen, Svalbard, are referred to the Oslobreen Group, which is composed of the Tokammane, Kirtonryggen and Valhallfonna formations. Herein we record the conodont succession of the Kirtonryggen and Valhallfonna formations. Collections of well-preserved conodonts (CAI 1) have been recovered from the Lower to lower Middle Ordovician interval in the region. Eight regional conodont zones are established in this preliminary study of the Oslobreen Group exposed at Hinlopenstretet, NE Svalbard. In ascending order these zones are: Rossodus manitouensis, Macerodus dianae, Oneotodus costatus, Oepikodus communis, O. evae, O. inter-medius, Periodon aff. flabellum-Periodon hankensis and Periodon macrodentatus. The yield is relatively poor for the Kirtonryggen Formation, but the oldest Ordovician conodont faunas span the Trema-docian Rossodus manitouesis through Macerodus dianae zones followed by the Floian Oepikodus communis Zone. The taxa are typical of the tropical North American Midcontinent faunal province that dominated the region until open marine associations invaded the shallow shelf (i.e. Evae transgression). The pandemic Oepikodus evae becomes frequent and is succeeded by O. intermedius in abundance in the lower Valhallfonna Formation (Olenidsletta Member). The upper strata are characterised by the Periodon-Paroistodus assemblage characteristic for outer shelf and slope environments around Laurentia. In total, this formation comprises the Floian and Dapingian stages and ends in the early Darriwilian Periodon macroden-tatus Zone in this region. The Ny Friesland faunas show affinities to coeval assemblages from Northeast Greenland and West Newfoundland. © 2013 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.
UnivIS-Import:2015-03-09:Pub.2013.nat.dgeo.IGM.LG.conodo
Keywords: Conodont biostratigraphy; Ny Friesland; Ordovician; Svalbard (Spitsbergen); Tremadocian

Conodonts in Silurian hypersaline environments: Specialized and unexpectedly diverse - Jarochowska, Emilia; Viira, Viive; Einasto, Rein; Nawrot, Rafał; Bremer, Oskar; Männik, Peep; Munnecke, Axel (Geology, 2017)
Hypersaline environments are commonly assumed to be barren of metazoans and therefore are avoided by paleontologists, yet a number of early Paleozoic jawless vertebrate groups specialized to live in such settings. Sampling bias against restricted settings resulted in substantial underestimation of their diversity. Rare studies venturing into such environments yielded multiple new species of conodonts, suggesting that the diversity and habitat range of these hyperdiverse predators of the early oceans are equally underestimated. We describe here autochthonous conodont fauna from evaporite-bearing horizons from the middle Silurian of Estonia that provide evidence for efficient osmoregulation in this group. Based on a global compilation of coeval conodont assemblages, we show that marginal-marine, periodically emergent environments were characterized by higher conodont diversity than open-marine shallow settings. This diversity is due to a high number of species occurring in these environments only. The high degree of specialization is also reflected by the highest within-habitat variability (β diversity) in marginal settings. Most conodont species had narrow environmental niches and, unlike in marine invertebrates, extreme environments were inhabited by the most specialized taxa. Such environments represent a large proportion of early Paleozoic tropical epicratonic basins. Our analysis allows quantification of the degree to which mid-Silurian conodont diversity is underestimated as a result of sampling bias against marginal-marine settings.
Keywords: Hypersaline environments; conodonts; invertebrates; quantification; Paleozoic; diversity; beta diversity; Estonia; Silurian

Conodont size reduction and diversity losses during the carnian humid episode in SW China - Zhang, Z. T.; Sun, Yadong; Wignall, P. B.; Fu, J. L.; Li, H. X.; Wang, M. Y.; Lai, X. L. (Journal of the Geological Society, 2018)

Considering Lithological Variability in Top Seal Analysis. - Drews, Michael; et al. (AAPG Annual Conference, 2014)

Constraining the Deep Origin of Parasitic Flatworms and Host-Interactions with Fossil Evidence. - de Baets, Kenneth; Dentzien-Dias, Paula; Upeniece, Ieva; Verneau, Olivier; Donoghue, Philip C. J. (Advances in Parasitology, 2015)
Novel fossil discoveries have contributed to our understanding of the evolutionary appearance of parasitism in flatworms. Furthermore, genetic analyses with greater coverage have shifted our views on the coevolution of parasitic flatworms and their hosts. The putative record of parasitic flatworms is consistent with extant host associations and so can be used to put constraints on the evolutionary origin of the parasites themselves. The future lies in new molecular clock analyses combined with additional discoveries of exceptionally preserved flatworms associated with hosts and coprolites. Besides direct evidence, the host fossil record and biogeography have the potential to constrain their evolutionary history, albeit with caution needed to avoid circularity, and a need for calibrations to be implemented in the most conservative way. This might result in imprecise, but accurate divergence estimates for the evolution of parasitic flatworms.

Constraints on mantle evolution from Ce-Nd-Hf isotope systematics - Willig, Michael; Stracke, Andreas; Beier, Christoph; Salters, Vincent J.M. (Geochimica Et Cosmochimica Acta, 2020)
Mantle evolution is governed by continuous depletion by partial melting and replenishment by recycling oceanic and continental crust. Several important unknowns remain, however, such as the extent of compositional variability of the residual depleted mantle, the timescale, mass flux and composition of recycled oceanic and continental crust. Here, we investigate the Ce-Nd-Hf isotope systematics in a globally representative spectrum of mid ocean ridge and ocean island basalts. Using a Monte Carlo approach for reproducing the observed Ce-Nd-Hf isotope variation shows that the type and age of depleted mantle and recycled crust have the dominant influence on the slope, scatter, and extent of the modeled Ce-Nd-Hf isotope array. The model results suggest a relatively young (<1.5 Ga) average depletion age of the depleted mantle, consistent with Nd and Os isotope model ages of abyssal peridotites, and an apparent moderate extent of incompatible element depletion. The latter, however, is deceiving, because it reflects a natural sampling bias, resulting from melting an inherently heterogeneous depleted mantle. In principal, recycling of oceanic crust can explain most of the isotopic range of the isotopically enriched end of the Ce-Nd-Hf mantle array, but only if the entire compositional variability of the recycled crust is preserved during recycling, residence in the mantle, and re-melting. The latter is unlikely, however, because many sources of internal chemical variance average out on the scale of the bulk oceanic crust, during residence in the mantle, and subsequent sampling by partial melting. Moreover, both the slope and limited scatter of the observed Ce-Nd-Hf mantle array show that recycling of bulk oceanic crust, that is, both the extrusive basalts and intrusive gabbros of the lower oceanic crust must be considered, and are key to better understand crust-mantle cycling in general. The Monte-Carlo simulation also indicates that the return flux from the continental crust into the mantle mainly derives from the lower continental crust, consistent with current models of continental crust evolution, which all require that a substantial amount of the mafic lower continental crust must be recycled into the mantle to maintain the average andesitic composition of the continental crust.
CRIS-Team Scopus Importer:2020-01-21
Keywords: Cerium isotopes; Depleted mantle; Mantle heterogeneity; MORB; OIB; REE

Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain - O'Connor, John; Steinberger, Bernhard; Regelous, Marcel; Koppers, Anthony A P; Wijbrans, Jan; Haase, Karsten; Stoffers, Peter; Jokat, Wilfried; Garbe-Schönberg, Dieter (Geochemistry Geophysics Geosystems, 2013)
Keywords: Hawaiian-Emperor seamounts; hot spots; mantle geodynamics; plate motion; plumes; seamounts

Constraints on Pennsylvanian glacioeustatic sea-level changes using oxygen isotopes of conodont apatite - Buggisch, Werner; von Bitter, Peter; Joachimski, Michael (Geology, 2006)
UnivIS-Import:2015-03-09:Pub.2006.nat.dgeo.IGM.LG.constr
Keywords: Conodonts; Oxygen isotopes; Pennsylvanian; Sea level

Constraints on the formation of geochemically variable plagiogranite intrusions in the Troodos Ophiolite, Cyprus - Freund, Sarah; Haase, Karsten; Keith, Manuel; Beier, Christoph; Garbe-Schönberg, Dieter (Contributions To Mineralogy and Petrology, 2014)
The geochemistry and petrology of tonalitic to trondhjemitic samples (n = 85) from eight different plagiogranite intrusions at the gabbro/sheeted dyke transition of the Troodos Ophiolite were studied in order to determine their petrogenetic relationship to the mafic plutonic section and the lava pile. The plagiogranitic rocks have higher SiO contents than the majority of the glasses of the Troodos lava pile, but lie on a continuation of the chemical trends defined by the extrusive rocks, indicating that the shallow intrusions generally represent crystallised magmas. We define three different groups of plagiogranites in the Troodos Ophiolite based on different incompatible element contents and ratios. The first and most common plagiogranite group has geochemical similarities to the tholeiitic lavas forming the lavas and sheeted dyke complex in the Troodos crust, implying that these magmas formed at a spreading axis. The second plagiogranite group occurs in one intrusion that is chemically related to late-stage and off-axis boninitic lavas and dykes. One intrusion next to the Arakapas fault zone consists of incompatible element-enriched plagiogranites which are unrelated to any known mafic crustal rocks. The similarities of incompatible element ratios between plagiogranites, lavas and mafic plutonic rocks, the continuous chemical trends defined by plagiogranites and mafic rocks, as well as incompatible element modelling results, all suggest that shallow fractional crystallisation is the dominant process responsible for formation of the felsic magmas. © 2014 Springer-Verlag Berlin Heidelberg.
Keywords: Crust formation; Fractional crystallisation; Magma evolution; Tonalite; Trondhjemite

Constraints on the magmatic evolution of the oceanic crust from plagiogranite intrusions in the Oman ophiolite - Haase, Karsten; Freund, Sarah; Beier, Christoph; Koepke, Juergen; Erdmann, Martin; Hauff, Folkmar (Contributions To Mineralogy and Petrology, 2016)
We present major and trace element as well as Sr, Nd, and Hf isotope data on a suite of 87 plutonic rock samples from 27 felsic crustal intrusions in seven blocks of the Oman ophiolite. The rock compositions of the sample suite including associated more mafic rocks range from 48 to 79 wt% SiO, i.e. from gabbros to tonalites. The samples are grouped into a Ti-rich and relatively light rare earth element (LREE)-enriched P1 group [(Ce/Yb) > 0.7] resembling the early V1 lavas, and a Ti-poor and LREE-depleted P2 group [(Ce/Yb) < 0.7] resembling the late-stage V2 lavas. Based on the geochemical differences and in agreement with previous structural and petrographic models, we define phase 1 (P1) and phase 2 (P2) plutonic rocks. Felsic magmas in both groups formed by extensive fractional crystallization of olivine, clinopyroxene, plagioclase, apatite, and Ti-magnetite from mafic melts. The incompatible element compositions of P1 rocks overlap with those from mid-ocean ridges but have higher Ba/Nb and Th/Nb trending towards the P2 rock compositions and indicating an influence of a subducting slab. The P2 rocks formed from a more depleted mantle source but show a more pronounced slab signature. These rocks also occur in the southern blocks (with the exception of the Tayin block) of the Oman ophiolite implying that the entire ophiolite formed above a subducting slab. Initial Nd and Hf isotope compositions suggest an Indian-MORB-type mantle source for the Oman ophiolite magmas. Isotope compositions and high Th/Nb in some P2 rocks indicate mixing of a melt from subducted sediment into this mantle.
Keywords: Fractional crystallization; Mid-ocean ridge; Subduction

Constraints on the Northwestern Atlantic Deep Water Circulation From Pa-231/Th-230 During the Last 30,000 Years - Suefke, Finn; Poeppelmeier, Frerk; Goepfert, Tyler Jay; Regelous, Marcel; Koutsodendris, Andreas; Blaser, Patrick; Gutjahr, Marcus; Lippold, Joerg (Paleoceanography and Paleoclimatology, 2019)
Global climatic changes during the last glacial and deglacial have been related to variations of the Atlantic Meridional Overturning Circulation (AMOC). Here, we present new and refined Pa-231/Th-230 down-core profiles extending back to 30 ka BP from the northwestern Atlantic along the Atlantic Deep Western Boundary Current, which is the main component of the southward deep backflow of the AMOC. Besides the well-known Bermuda Rise records, available high-resolution Pa-231/Th-230 data in the northwestern Atlantic are still sparse. Our new records along with reconstructions of deep water provenance from Nd isotopes constrain the timing and magnitude of past changes in AMOC from an additional northwestern Atlantic region forming a depth transect between 3,000- and 4,760-m water depth. Our extended and improved data set confirms the weakening of the AMOC during deglacial cold spells such as Heinrich Event 1 and the Younger Dryas interrupted by a reinvigoration during the Bolling-Allerod interstadial as seen in the prominent Pa-231/Th-230 records from the Bermuda Rise. However, in contrast to the Bermuda Rise records, we find a clearly reduced circulation strength during the Last Glacial Maximum in the deep Atlantic.
CRIS-Team WoS Importer:2019-12-17

Constraints on the source of Cu in a submarine magmatic-hydrothermal system, Brothers volcano, Kermadec island arc - Keith, Manuel; Haase, Karsten; Klemd, Reiner; Smith, Dan; Schwarz-Schampera, Ulrich; Bach, Wolfgang (Contributions To Mineralogy and Petrology, 2018)
Most magmatic-hydrothermal Cu deposits are genetically linked to arc magmas. However, most continental or oceanic arc magmas are barren, and hence new methods have to be developed to distinguish between barren and mineralised arc systems. Source composition, melting conditions, the timing of S saturation and an initial chalcophile element-enrichment represent important parameters that control the potential of a subduction setting to host an economically valuable deposit. Brothers volcano in the Kermadec island arc is one of the best-studied examples of arc-related submarine magmatic-hydrothermal activity. This study, for the first time, compares the chemical and mineralogical composition of the Brothers seafloor massive sulphides and the associated dacitic to rhyolitic lavas that host the hydrothermal system. Incompatible trace element ratios, such as La/Sm and Ce/Pb, indicate that the basaltic melts from L'Esperance volcano may represent a parental analogue to the more evolved Brothers lavas. Copper-rich magmatic sulphides (Cu > 2 wt%) identified in fresh volcanic glass and phenocryst phases, such as clinopyroxene, plagioclase and Fe-Ti oxide suggest that the surrounding lavas that host the Brothers hydrothermal system represent a potential Cu source for the sulphide ores at the seafloor. Thermodynamic calculations reveal that the Brothers melts reached volatile saturation during their evolution. Melt inclusion data and the occurrence of sulphides along vesicle margins indicate that an exsolving volatile phase extracted Cu from the silicate melt and probably contributed it to the overlying hydrothermal system. Hence, the formation of the Cu-rich seafloor massive sulphides (up to 35.6 wt%) is probably due to the contribution of Cu from a bimodal source including wall rock leaching and magmatic degassing, in a mineralisation style that is hybrid between Cyprus-type volcanic-hosted massive sulphide and subaerial epithermal-porphyry deposits.
Keywords: Brothers volcano; Kermadec arc; Magmatic sulphides; Hydrothermal sulphides; Magmatic degassing; Melt inclusions; Epithermal-porphyry deposits; VHMS deposits

Continental rift-setting and evolution of neoproterozoic Sindreth basin in NW-India - Schöbel, Stefan; Sharma, Kamal K.; Hörbrand, Thorsten; Böhm, Theresa; Donhauser, Ines; de Wall, Helga (Journal of Earth System Science, 2017)
Keywords: Basin evolution; Continental setting; Malani Igneous Suite; NW India; Sindreth Basin

Continuous evolutionary change in Plio-Pleistocene mammals of eastern Africa - Bibi, Faysal; Kießling, Wolfgang (Proceedings of the National Academy of Sciences of the United States of America, 2015)
UnivIS-Import:2016-06-01:Pub.2015.nat.dgeo.IGM.LP.contin
Keywords: Africa; Bovidae; Mammals; Plio-Pleistocene; Turnover

Contrasting shallow and deeper water marine assemblages of the highly heterogeneous biota from the Late Triassic Cassian Formation, northern Italy - Nützel, Alexander; Hausmann, Imelda M.; Reich, Mike; Roden, Vanessa (GeoBonn 2018, Living Earth - Abstracts, 2018)

Contrasting stress fields on correlating margins of the South Atlantic - Salomon, Eric; Koehn, Daniel; Passchier, Cees; Hackspacher, Peter Christian; Glasmacher, Ulrich Anton (Gondwana Research, 2015)
The "passiveness" of passive continental margins across the globe is currently under debate since several studies have shown that these margins may experience a variety of stress states and undergo significant vertical movement post-breakup. Of special interest is the South Atlantic, because the bounding continents have very different recent geological histories, with Africa experiencing continental rifting whereas South America is influenced by subduction on the Pacific side. It is not clear to what extent the Atlantic continental margins are subject to the same stresses and vertical motions as the main continents. To address this problem, we performed a paleostress analysis of two originally adjacent areas, i.e. NW Namibia and SE/S Brazil. Both areas are covered by the similar to 133-Ma-old Parana-Etendeka extrusives-that were emplaced shortly before or during the onset of the Atlantic rifting. Thus, the volcanics serve as a time marker for syn- or post-rift deformation. Collected fault slip data in the volcanics reveal remarkable differences between the two correlating areas. NW Namibia was dominated by extension in ENE-WSW and SW-NE directions, and by minor strike-slip movement with NW-SE directed compression. SE/S Brazil was mostly affected by strike-slip faulting, with compression oriented E-W and SW-NE. Similar fault systems appear widespread across SE Brazil and may be the combined result of flexural margin bending and the Nazca plate subduction. The results of NW Namibia differ from known compressional stress tensors in western South Africa, post-dating 90 Ma. The south-western African continental margin may thus have experienced a spatially variable stress history. Our results show that the tectonic evolution of the continental margins of the South Atlantic is not passive and that both margins vary significantly in structural style and stress fields, indicating that variable plate boundary forces play a major role in margin evolution. (C) 2014 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
Keywords: Paleostress; Passive margin; South Atlantic; Namibia; Brazil

Contrasting styles of ephemeral river systems and their interaction with dunes of the Skeleton Coast erg (Namibia). - Krapf, Carmen; Stollhofen, Harald; Stanistreet, Ian G. (Quaternary international, 2003)
The Skeleton Coast erg forms a prominent NNW trending dune belt, 6-22 km wide, comprising dunes up to 50 m high, sub- parallel to the South Atlantic margin of Namibia. To a variable degree along its strike, the dune belt dams west-southwestward flowing ephemeral river systems on their route towards the Atlantic Ocean. The southern rivers, Koigab, Uniab and Hunkab, affecting the erg, are characterized by short, infrequent ephemeral flows from restricted catchments, whereas northern rivers, Hoanib and Hoarusib, are fed by large catchment areas favouring higher discharge and more frequent flows as the intertropical convergence zone and greater likelihood of monsoonal rainfall influence is approached. The potential for river damming increases in the same downwind direction through the erg because of increasing dune belt width and height and the change from low barchanoid dune forms in the south to large composite transverse dunes in the north. Whereas cross-sections of the southern part of the erg show considerable asymmetry with low barchans and sinuous crested dune forms eastwards but a high dune wall at the western edge, cross-sections over the northern erg are more uniformly symmetrical. As a consequence, the northern rivers are effectively dammed at the eastern erg margin, causing flood reservoir basins there. In contrast, southern rivers are dammed within the erg as the most pronounced and commonly encountered barrier is provided by the dunewall at its western border. © 2002 Elsevier Science Ltd and INQUA. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2003.nat.dgeo.IGM.LG.contra

Contribution of microbialites to the development of coral reefs during the last deglacial period: case study from Vanuatu (South West Pacific). - Joachimski, Michael; et al. (Sedimentary Geology, 2006)
Coral reefs have grown continuously during the Last 24 ka on the island of Espiritu Santo (Vanuatu, South-West Pacific) in a setting characterized by frequent tectonic uplifts related to subduction of the Australia plate beneath the Vanuatu Island arc. Sedimentological and geochemical studies of two neighbouring areas having much different mean uplift rates and environmental settings provides an opportunity to analyze the environmental factors that promoted the widespread development of microbialite crusts from about 24 to 6 ka B.P. Nutrient supplies, and probably the rapidity of the sea level rise, are critical to an explanation of the distinctive distribution of microbialites in reef cores. Nutrient flux has been related to terrigenous fluxes in the Tasmaloum reef system that fringed the south-west uplifting coast of Espiritu Santo and possibly to upwelling in the Urélapa sequence that was isolated from the main island during its growth. A peak in microbialite abundance occurred between 16 and 10 ka B.P., a time window characterized by increasing erosional processes and/or more intense upwelling during a very rapid rise in sea-level. Crown Copyright © 2005 Published by Elsevier B.V. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2006.nat.dgeo.IGM.LG.contri
Keywords: Coral reef; Deglacial; Microbialite; South-West Pacific; Vanuatu

Contributions to one health approach to solve geogenie health issues - Chandrajith, Rohana; Barth, Johannes (wiley, 2023)
"One Health" is a concept that developed during the last two decades. It considers the health of humans, animals, and the ecosystem as a whole, where health issues cannot be tackled in isolation. The geogenic environment that is represented by the lithosphere, hydrosphere, and atmosphere is an important component and has direct links with noncommunicable chronic health issues among humans and animals. For instance, excess or lack of particular elements, such as fluoride in the geogenic environment, plays an important role in health as exemplified by dental and skeletal fluorosis. Other examples include the consumption of arsenic-contaminated water that can lead to cancer and high background radiation caused by uranium and radon. In this chapter, we provide an overview and highlight the importance of the geochemistry of the living environment and its contribution to the "One Health" concept.
CRIS-Team Scopus Importer:2023-07-21
Keywords: Dental and skeletal fluorosis; Dose-response relationship; Medical geology; Radon and health

CONTROLLED ACTIVATION OF PREFABRICATED A-TRICALCIUM PHOSPHATE CEMENT PASTES STABILIZED BY SODIUM PYROPHOSPHATE - Hurle, Katrin; Weichhold, Jan; Götz-Neunhoeffer, Friedlinde; Gbureck, Uwe (TISSUE ENGINEERING PART A, 2022)
CRIS-Team WoS Importer:2022-08-12

Controlling ettringite precipitation and rheological behavior in ordinary Portland cement paste by hydration control agent, temperature and mixing - Jakob, Cordula; Jansen, Daniel; Dengler, Joachim; Neubauer, Jürgen (Cement and Concrete Research, 2023)
The influence of ettringite precipitation on the rheological properties during the initial and the induction period of ordinary Portland cement (OPC) hydration is examined by combining quantitative X-ray diffraction (QXRD), thermogravimetry (TG), calorimetry, penetration test method and 1H-TD-NMR. This allows a good overview about mineralogical changes during hydration and conclusions about their effect on rheological and microstructural changes within the paste. The reaction kinetic are controlled either by varying curing temperature or by an organic additive, which allows adjustment of the initial aluminate reaction while delaying the silicate reaction for hours. A significant correlation of ettringite content and rheological behavior due to structural build-up of the paste is observed in all investigated systems. The potential influence of ettringite content on structural build-up of the paste is found to be comparable to the effect of solid volume fraction on rheology (viscosity & yield stress).
CRIS-Team Scopus Importer:2023-01-27
Keywords: Ettringite; Hydration kinetics; OPC; Organic additive; Rheology

Controls of evaporative irrigation return flows in comparison to seawater intrusion in coastal karstic aquifers in northern Sri Lanka: Evidence from solutes and stable isotopes - Chandrajith, Rohana; Diyabalanage, Saranga; Premathilake, K. M.; Hanke, Christian; van Geldern, Robert; Barth, Johannes (Science of the Total Environment, 2016)

Controls of mud mound formation: the Early Devonian Kess-Kess carbonates of the Hamar Laghdad, Antiatlas, Morocco. - Buggisch, Werner; Joachimski, Michael; et al. (Geologische Rundschau, 1992)
The origin and development of Early Devonian (late Pragian to late Zlichovian; predominantly uppermost Zlichovian as indicated by conodont faunas) mud mounds of the Hamar Laghdad area in the eastern Antiatlas, Morocco, are controlled by extrinsic and intrinsic factors. Extrinsic factors include the existence of a paleohigh (Lochkovian volcaniclastics), unidirectional currents and repeated storm events as well as sea level fluctuations. Intrinsic, biologically induced factors are the preferred growth of organisms on the top and the flanks of the mounds because of more favourable ecological conditions, and a rapid synsedimentary lithification of the steep mound flanks by interskeletal cementation of auloporid tabulate corals. The mounds developed in an epicontinental basin below the wave base but within the range of storms. The formation of the mounds started within the uppermost part of the bedded crinoid facies of the Kess-Kess Formation with the hydrological accumulation of a bioclastic pile. This elevation became settled by crinoids and high-diverse tabulate corals producing bioclastic sediment. Binding activities of the organisms were missing, calcareous algae and stromatoporoids are completely absent. Baffling by thamnoporid tabulate corals might have occurred locally but was not important for the development of the mounds. Steep slopes to the north and less steep slopes to the south may be the result of north-northwest to south-southeast trending currents, derived from orientation patterns of orthocone nautiloids in the uppermost beds of the Kess-Kess Formation. A synsedimentary cementation of the flanks, possibly triggered by submarine interskeletal cementation of patchily distributed auloporid colonies, protected the bioclastic sediment against redistribution by frequent storms (indicated by densely spaced eventstone intervals and partly also by the common »Stromatactis«-like structures within the mound facies). Accumulation of more parautochthonous bioclastic sediment within the mounds as compared to the intermound area, therefore, is caused by a selfsustaining system of hydrologic piling of sediment triggered by storms, preferred settlement of organisms upon these piles, producing bioclastic sediment and coeval biocementation of the growing mound flanks. This model differs from existing mud mound models in the lack or only minor significance of binding and baffling, in the lack of mound facies sequences and in the greater importance of extrinsic control factors. © 1992 Ferdinand Enke Verlag Stuttgart.
UnivIS-Import:2015-03-05:Pub.1992.nat.dgeo.IGM.LG.contro

Controls on carbon cycling in two contrasting temperate zone estuaries: The Tyne and Tweed, UK - Barth, Johannes; et al. (Estuarine Coastal and Shelf Science, 2008)

Controls on Gas Emission Distribution on the Continental Slope of the Western Black Sea - Riedel, Michael; Hähnel, Line; Bialas, Jörg; Bachmann, Anna Katharina; Gaide, Stefanie; Wintersteller, Paul; Klaucke, Ingo; Bohrmann, Gerhard (Frontiers in Earth Science, 2021)
The continental slopes of the Black Sea show abundant manifestations of gas seepage in water depth of <720 m, but underlying controls are still not fully understood. Here, we investigate gas seepage along the Bulgarian and Romanian Black Sea margin using acoustic multibeam water column, bathymetry, backscatter, and sub-bottom profiler data to determine linkages between sub-seafloor structures, seafloor gas seeps, and gas discharge into the water column. More than 10,000 seepage sites over an area of ∼3,000 km2 were identified. The maximum water depth of gas seepage is controlled by the onset of the structure I gas hydrate stability zone in ∼720 m depth. However, gas seepage is not randomly distributed elsewhere. We classify three factors controlling on gas seepage locations into depositional, erosional, and tectonic factors. Depositional factors are associated with regionally occurring sediment waves forming focusing effects and mass-transport deposits (MTDs) with limited sediment drape. Elongated seafloor depressions linked to faulting and gas seepage develop at the base between adjacent sediment waves. The elongated depressions become progressively wider and deeper toward shallow water depths and culminate in some locations into clusters of pockmarks. MTDs cover larger regions and level out paleo-topography. Their surface morphology results in fault-like deformation patterns of the sediment drape on top of the MTDs that is locally utilized for gas migration. Erosional factors are seen along channels and canyons as well as slope failures, where gas discharge occurs along head-scarps and ridges. Sediment that was removed by slope failures cover larger regions down-slope. Those regions are devoid of gas seepage either by forming impermeable barriers to gas migration or by removal of the formerly gas-rich sediments. Deep-rooted tectonic control on gas migration is seen in the eastern study region with wide-spread normal faulting promoting gas migration. Overall, gas seepage is widespread along the margin. Gas migration appears more vigorous in shallow waters below ∼160 m water depth, but the number of flare sites is not necessarily an indicator of the total volume of gas released.
CRIS-Team Scopus Importer:2021-03-19
Keywords: black sea; Danube deep-sea fan; faulting; gas hydrates; gas venting; structural control

Controls on melting at spreading ridges from correlated abyssal peridotite - mid-ocean ridge basalt compositions - Regelous, Marcel; Weinzierl, Christoph; Haase, Karsten (Earth and Planetary Science Letters, 2016)
Variations in the volume and major element composition of basalt erupted along the global mid-ocean ridge system have been attributed to differences in mantle potential temperature, mantle composition, or plate spreading rate and lithosphere thickness. Abyssal peridotites, the residues of mantle melting beneath mid-ocean ridges, provide additional information on the melting process, which could be used to test these hypotheses. We compiled a global database of abyssal peridotite compositions averaged over the same ridge segments defined by Gale et al. (2013). In addition, we calculated the distance of each ridge segment to the nearest hotspots.We show that Cr# in spinel in abyssal peridotites is negatively correlated with Na in basalts from the same ridge segments on a global scale. Ridge segments that erupt basalts apparently produced by larger degrees of mantle melting are thus underlain by peridotites from which large amounts of melt have been extracted. We find that near-ridge hotspots have a more widespread influence on mid-ocean ridge basalt (MORB) composition and ridge depth than previously thought. However, when these hotspot-influenced ridge segments are excluded, the remaining segments show clear relationships between MORB composition, peridotite composition, and ridge depth with spreading rate. Very slow-spreading ridges (<20 mm/yr) are deeper, erupt basalts with higher Na, Al, K/Ti, and lower Fe, Ca/Al, and expose peridotites with lower Cr# than intermediate and fast-spreading ridges.We show that away from hotspots, the spreading-rate dependence of the maximum degree of mantle melting inferred from Cr# in peridotites (F) and the bulk degree of melting inferred from Na in basalts (F) from the same ridge segments is unlikely to be due to variations in mantle composition. Nor can the effects of dynamic mantle upwelling or incomplete melt extraction at low spreading rates satisfactorily explain the observed compositions of abyssal peridotites and MORB from very slow-spreading ridges. Instead, the distinctive compositions of abyssal peridotites and MORB from very slow-spreading ridges could result from the presence of a thick lithospheric lid, leading to a lower average degree of melting, and a higher contribution to melting from more fertile mantle lithologies. Alternatively, spreading rate influences the thermal structure of the upper mantle such that the mantle beneath very slow-spreading ridges is cooler.
Keywords: Abyssal peridotites; Geochemistry; Hotspots; Mantle heterogeneity; Mid-ocean ridge basalts; Spreading rate

Controls on reservoir compartmentalization of an upper Permian tight gas field in Germany and links to a modern analogue in the western U.S. - Antrett, Philipp; Vackiner, Anna Alexandra; Kukla, Peter; Back, Stefan; Stollhofen, Harald (Petroleum Geoscience, 2012)
This study focuses on the reservoir characteristics of a Permian tight gas field in the Southern Permian Basin, Eastern Frisia, Germany. To improve the understanding of the reservoir, 3D seismic, wireline and core data were compared with a reservoir analogue in the Panamint Valley, United States. Depositional environments of the Permian Upper Rotliegend II include perennial saline lakes, coastal parallel sand belts comprising wet, damp and dry sand flats and aeolian dunes with interdune deposits. Polygonal patterns at different scales were observed on seismic horizon slices in the reservoir intervals and the overlying Zechstein. Outlines of superordinate polygons coincide with interpreted faults. Similar polygonal networks were identified on modern dry lakes in the western United States. The kilometre-long, up to 1.20 m deep open fissures in the Panamint Valley are interpreted to originate from the combined effects of synaeresis and tectonics. Subsequently, the fissures were filled with aeolian sediment. Vegetation growth confined to the lineaments indicates enhanced fluid circulation. Such fissures systems may serve as weakness zones and fault grain and impact reservoir quality in terms of hydraulic connectivity of reservoir compartments. For the Rotliegend reservoirs, original porosities and permeabilities of these zones were reduced to a minimum by enhanced cementation along the fluid migration pathways. Permeability barriers and reservoir compartmentalization, which can be clearly depicted on seismic attribute volumes, are a potential result of this development.
UnivIS-Import:2015-03-09:Pub.2012.nat.dgeo.IGM.LG.newins

Cool episode and platform demise in the Early Aptian: New insights on the links between climate and carbonate production - Bonin, Aurelie; Puceat, Emmanuelle; Vennin, Emmanuelle; Mattioli, Emanuela; Aurell, Marcos; Joachimski, Michael; Barbarin, Nicolas; Laffont, Remi (Paleoceanography, 2016)
The Early Aptian encountered several crises in neritic and pelagic carbonate production, major perturbations in the carbon cycle, and an oceanic anoxic event (OAE1a). Yet the causal links between these perturbations and climate changes remain poorly understood, partly because temperature records spanning the Early Aptian interval are still scant. We present new δO data from well-preserved bivalves from a carbonate platform of the Galve subbasin (Spain) that document a major cooling event postdating most of OAE1a. Our data show that cooling postdates the global platform demise and cannot have triggered this event that occurred during the warmest interval. The warmest temperatures coincide with the time equivalent of OAE1a and with platform biotic assemblages dominated by microbialites at Aliaga as well as on other Tethyan platforms. Coral-dominated assemblages then replace microbialites during the subsequent cooling. Nannoconids are absent during most of the time equivalent of the OAE1a, probably related to the well-known crisis affecting this group. Yet they present a transient recovery in the upper part of this interval with an increase in both size and abundance during the cool interval portion that postdates OAE1a. An evolution toward cooler and drier climatic conditions may have induced the regional change from microbial to coral assemblages as well as nannoconids size and abundance increase by limiting continent-derived input of nutrients.
Keywords: Aptian; oxygen isotopes; palaeoclimate; platform demise

Coral community shifts across major reef crises - Dimitrijevic, Danijela; Raja Schoob, Nussaibah Begum; Kießling, Wolfgang (ICRS 2021, 14th International Coral Reef Symposium, 2021)
Coral communities today are negatively affected by anthropogenic greenhouse gas release causing global warming and ocean acidification. Natural greenhouse gas release by massive volcanism is thought to have caused one of the Big Five mass extinctions at the end of the Triassic period (200 million years ago). This hyperthermal event triggered one of the greatest reef crises and the most substantial evolutionary crisis in the history of scleractinian corals. While the diversity dynamics of corals are well studied, research on changes in community composition at this time is still lacking. We provide a quantitative assessment of community changes at the level of morphological traits (ie corallite sizes, growth form, and colony form). Using our new Reef Traits Database (RTD), we show that corallite sizes of colonial corals increased substantially after the end-Triassic reef crisis. We conclude that a change towards increasing heterotrophy in reef coral communities best explains the observations across the end-Triassic reef crisis. Additionally, we test how much of the trend in corallite size is governed by selective extinction, origination, and changes in relative abundance across coral communities. Therefore, the fossil record showcases the balance of evolutionary adaptation versus extinction and the lasting community changes in response to climate change over longer time frames than we could cover by studying the extant coral communities. We conclude that a change towards increasing heterotrophy in reef coral communities best explains the observations across the end-Triassic reef crisis. Additionally, we test how much of the trend in corallite size is governed by selective extinction, origination, and changes in relative abundance across coral communities. Therefore, the fossil record showcases the balance of evolutionary adaptation versus extinction and the lasting community changes in response to climate change over longer time frames than we could cover by studying the extant coral communities. We conclude that a change towards increasing heterotrophy in reef coral communities best explains the observations across the end-Triassic reef crisis. Additionally, we test how much of the trend in corallite size is governed by selective extinction, origination, and changes in relative abundance across coral communities. Therefore, the fossil record showcases the balance of evolutionary adaptation versus extinction and the lasting community changes in response to climate change over longer time frames than we could cover by studying the extant coral communities.<br

Coralline red algae as high-resolution climate recorders - Halfar, Jochen; Steneck, R. S.; Joachimski, Michael; Kronz, A.; Wanamaker, A. D. (Geology, 2008)
Most high-resolution, proxy-based paleoclimate research has concentrated on tropical oceans, while mid-and high-latitude marine regions have received less attention, despite their importance in the global climate system. At present, sclerochronological analyses of bivalve mollusks supply the bulk of annual-to subannual-resolution extratropical marine climate data, even though interpretation is complicated by a slowdown of growth with increasing shell age. Hence, in order to address the need for additional high-resolution proxy climate data from extratropical regions, we conducted the first year-long in situ field calibration of the coralline red alga Clathromorphum compactum in the Gulf of Maine, United States. Coralline red algae are widely distributed in coastal regions worldwide, and individual calcified plants can live continuously for several centuries in temperate and subarctic oceans. Stable oxygen isotopes extracted at subannual resolution from growth increments of monitored specimens of C. compactum relate well to in situ-measured sea-surface temperatures during the May to December calcification period, highlighting the suitability of coralline red algae as an extratropical climate archive. Furthermore, there is a strong correlation between a 30 yr δ18O record of C. compactum and an instrumental sea-surface temperature record (r = -0.58,p = 0.0008) and a proxy reconstruction derived from the bivalve Arctica islandica collected in the central Gulf of Maine (r = 0.54,p = 0.002). © 2008 The Geological Society of America.
UnivIS-Import:2015-03-09:Pub.2008.nat.dgeo.IGM.LG.corall
Keywords: Clathromorphum; Coralline red algae; Gulf of Maine; Paleoclimate; Sclerochronology

Coralline red algae from the Silurian of Gotland indicate that the order Corallinales (Corallinophycidae, Rhodophyta) is much older than previously thought - Teichert, Sebastian; Woelkerling, William; Munnecke, Axel (Palaeontology, 2019)
Aguirrea fluegelii gen. et sp. nov. (Corallinales, Corallinophycidae, Rhodophyta) is described from the mid‐Silurian of Gotland Island, Sweden (Högklint Formation, lower Wenlock). The holotype is of dimerous construction and includes a uniporate conceptacle with a sporangium, thus providing evidence that taxa of the Corallinales/Corallinaceae existed at least 300 million years earlier than previously documented. Aguirrea fluegelii cannot be unequivocally placed in any of seven currently recognized lineages/subfamilies/groups of the Corallinaceae as not all diagnostic characters are preserved, and thus is accorded incertae sedis status within the family Corallinaceae and order Corallinales. Extant evolutionary history studies of Corallinophycidae involving molecular clocks now require updating using new calibration points to take account of the much earlier unequivocal mid‐Silurian record of uniporate conceptacle‐bearing taxa of Corallinales/Corallinaceae as well as the parallel record of Graticula, a genus attributed to the Sporolithale
Keywords: Aguirrea fluegelii; conceptacles; Corallinaceae; Corallinales; coralline red algae; Gotland

Corallite sizes and their link to extinction risk of scleractinian corals across the Triassic-Jurassic boundary - Dimitrijevic, Danijela; Raja, Nussaïbah Begum; Kießling, Wolfgang (GSA 2020 Connects Online, 2020)
The end-Triassic mass extinction and reef crisis was a significant crisis in the evolution of scleractinian corals. The crisis is thought to have been caused by volcanically induced global warming. Accordingly, we would expect photosymbiotic corals to be more strongly affected than non-symbiotic corals. However, although corallite integration has decreased across the Triassic-Jurassic boundary, the extinction of scleractinian corals seems to be non-selective with regards to their inferred photosymbiotic mode. Using our new Reef Traits Database (RTD) we test how corallite sizes may have changed across the Triassic-Jurassic boundary. Corallite sizes have been used as a proxy for the efficacy of photosymbiosis with smaller corallite sizes associated with higher photosymbiotic autotrophy in colonial corals. As such, we use maximum corallite diameter to investigate how the dependency on a photosynthetic diet may have increased the extinction risk of certain corals at the end-Triassic mass extinction. Based on a survey of nearly 2000 measurements we establish trends in corallite sizes across the Triassic-Jurassic. We find that there was a significant increase of corallite diameter at the Triassic-Jurassic boundary suggesting stronger heterotrophy. Corallite sizes were 1.8 times larger after the mass extinction, which is the strongest change across the entire 100 myr interval. Generalized linear modeling suggests that the increase of corallite diameters was due to the selective extinction of corals with smaller corallite

Corallite sizes of reef corals: decoupling of evolutionary and ecological trends - Dimitrijevic, Danijela; Raja Schoob, Nussaibah Begum; Kießling, Wolfgang (Paleobiology, 2023)
Corallite sizes reflect a continuum in the efficacy of photosymbiosis in colonial reef corals, with smaller corallite sizes generally associated with higher autotrophy. Using a large compilation of reef-coral traits and corallite diameters as a proxy, we test here the hypothesis that photosymbiotic efficacy has increased over the evolutionary history of scleractinian corals. To gain a more comprehensive understanding of the evolutionary versus ecological patterns of corallite sizes of reef corals, we used three analytical methods: (1) occurrences-weighted within-bin analyses as a proxy for abundance or ecological dominance to depict ecological patterns; (2) unweighted range-through analyses; and (3) unweighted sampled-in-bin analyses to represent diversity in terms of taxonomic richness, enabling us to trace evolutionary patterns. By-genus, range-through analysis indicates a slightly positive trend of corallite sizes toward the Recent. However, the occurrences-weighted assessment shows a pronounced negative trend of corallite sizes in colonial corals since the Mesozoic. Random walk and directional evolution are both statistically supported to explain this long-term decrease. A driven trend is evolutionarily plausible, giving reef corals a selective advantage in the oligotrophic environments they largely occupy today.

Coral Patch and Ormonde seamounts as a product of the Madeira hotspot, Eastern Atlantic Ocean - D'Oriano, Filippo; Angeletti, Lorenzo; Capotondi, Lucilla; Laurenzi, Marinella A.; López Correa, Matthias; Taviani, Marco; Torelli, Luigi; Trua, Teresa; Vigliotti, Luigi; Zittelini, Nevio (Terra Nova, 2010)
New detailed swath bathymetry and bottom samples from Coral Patch and Ormonde seamounts provide constraints on the emplacement of the Madeira hotspot in the Eastern Atlantic Ocean. Swath bathymetric data document that Coral Patch is a composite structure, made up of at least nine distinct volcanic centres. Lithified pelagic carbonates infilling fissures in lava blocks constrain a minimal age for the volcanism in the Early Miocene and represent the first documentation of Coral Patch acting as an offshore terrigenous-starved seamount. At Coral Patch, as already observed at the Ormonde seamount, volcanism was emplaced on top of a pre-existing relief resulting from the regional tectonic compressive regime. © 2010 Blackwell Publishing Ltd.
UnivIS-Import:2015-03-09:Pub.2010.nat.dgeo.IGM.LP.coralp
Keywords: seamounts; cold-water corals

Coral Reefs - Kießling, Wolfgang; Heiss, Georg A. (Biodiversity and Ecosystem Insecurity: A planet in peril, 2011)
Keywords: Coral reefs; Biodiversity; Crisis

Core stratigraphy constrains Bed IV archaeological record at HEB site, Olduvai Gorge, Tanzania - Njau, Jackson K.; Herrmann, Edward W.; Ruck, Lana; Pante, Michael C.; Farrugia, Paul; Toth, Nicholas; Schick, Kathy; Stollhofen, Harald; Stanistreet, Ian G. (Palaeogeography, Palaeoclimatology, Palaeoecology, 2020)
The Olduvai Gorge deposits contain a rich archaeological record documenting the evolution of hominin behavior over the last 2 million years. While archaeological assemblages in the lower sedimentary layers (Beds I-II) are well preserved in relatively secure chronostratigraphic contexts, the age of overlying beds is poorly constrained due to discontinuous exposures and lack of marker horizons, abundant erosional contacts and lack of unweathered, dateable material. As a result, Beds III-IV and the Masek Beds, have yet received little attention compared to the underlying beds. Recently, the Olduvai Gorge Coring Project (OGCP) acquired high resolution, stratigraphically continuous sedimentary cores of Palaeolake Olduvai through scientific drilling, in order to improve the geological and palaeoenvironmental contexts of the hominin record. While other studies reported in this volume have used palaeoenvironmental datasets from the cores to refine the Beds I-II records, this study combines outcrop and core stratigraphic methods to improve the chronology of Bed IV archaeological sites. Our recent excavation at HEB site demonstrates the importance of this approach to improve the stratigraphic positioning and relative age of Bed IV archaeological materials. Our results suggest that the HEB site is younger than previously thought because it was formed after depositional fill of an incised valley, which substantially removed much of lowermost Bed IV in the HEB area. The lithofacies at this site indicate lake expansion and development of Ngorongoro Highland sourced braided streams near the lakeshore at this time, which coincided with rich assemblages of artifacts, fossil fauna, and bones bearing butchery marks. This setting likely afforded a variety of resources to hominins including potable water, raw materials, refuge trees, and animal food, making HEB an important site for inferring the cultural and feeding behaviors of Homo erectus.<br
Keywords: Acheulean; Hominin; Homo erectus; Cut marks; Evolution

Coring tools have an effect on lithification and physical properties of marine carbonate sediments - De Vleeschouwer, David; Nohl, Theresa; Schulbert, Christian; M. Bialik, Or; Auer, Gerald (Scientific Drilling, 2023)
The International Ocean Discovery Program (IODP) JOIDES Resolution Science Operator typically uses an advanced piston corer (APC) in soft ooze and sediments and an extended core barrel (XCB) in firm sediments. The coring tool exchange typically occurs around the same depth in adjacent holes of the same site. However, during IODP Expedition 356, the coring tool switch occurred at different depths: IODP Sites U1463 and U1464 are marked by a stratigraphic interval (> 25 m thick) that was XCB cored in one hole and APC cored in other holes. Shipboard scientists remarked that APC-cored sediments were unlithified or partially lithified, while XCB-cored sediments were fully lithified. This difference in sedimentological description of the same formation seems to be an effect of coring technique. To provide further insight, we assessed the physical properties (bulk density, porosity, and P-wave velocity), downhole wireline logging data, scanning electron microscope (SEM) images, and micro-computed tomography (µCT) scans of those intervals. We find systematic differences between the different coring techniques. XCB cores are characterized by systematically lower bulk density, higher porosity, and higher P-wave velocity than APC cores. Downhole logging data suggest that the original P-wave velocity of the formation is better preserved in XCB cores, despite the typical “biscuit-and-gravy” core disturbance (i.e. well-preserved core fragments surrounded by squelched core material). In conjunction with SEM and µCT images, we conclude that the APC tool destroyed early lithification by breaking cements between individual grains. Moreover, µCT images reveal denser packing and smaller pore volumes in the APC cores. These sedimentary changes likely occur when the APC pressure wave passes through the sediment. The destruction of grain-to-grain cements provides an explanation for the significantly lower P-wave velocities in APC cores. Interestingly, the gravy sections in XCB drilled cores mimic the destruction of early lithification and reduction of pore volume. We conclude that APC remains the tool of choice for recovering soft sediments, especially for paleoclimate purposes. However, for the study of lithification, XCB biscuits provide a more representative image of the formation. For the study of early diagenesis, further studies are required to ascertain the preservation of key sedimentary features using existing and new drilling tool

Correction to: Do Skeletal Mg/Ca Ratios of Arctic Rhodoliths Reflect Atmospheric CO2 Concentrations? (Polar Biology, (2020), 43, 12, (2059-2069), 10.1007/s00300-020-02767-3) - Teichert, Sebastian; Voigt, Nora; Wisshak, Max (Polar Biology, 2021)
The article “Do skeletal Mg/Ca ratios of Arctic rhodoliths reflect atmospheric CO2 concentrations?”, written by Sebastian Teichert, Nora Voigt and Max Wisshak, was originally published Online First without Open Access. After publication in volume 43, issue 12, page 2059–2069 the author decided to opt for Open Choice and to make the article an Open Access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0. Open access funding enabled and organized by Projekt DEAL. The original article has been corrected.
CRIS-Team Scopus Importer:2021-07-09

Correction to manuscript “Recharge velocity and geochemical evolution for the Permo-Triassic Sherwood Sandstone, Northern Ireland” - Barth, Johannes; et al. (Journal of Hydrology, 2006)

Correction to: Reef refugia in the aftermath of past episodes of global warming (Coral Reefs, (2024), 43, 5, (1431-1442), 10.1007/s00338-024-02548-y) - Dimitrijevic, Danijela; Santodomingo, Nadia; Kießling, Wolfgang (Coral Reefs, 2024)
The original article has been corrected. In Fig. 2, the y-axis names were inadvertently inverted during proofing. In Fig. 2.a, the y-axis was published as "0–50–100–150" and should have been "0–20–40–60–80–100". In Fig. 2.b, the y-axis was published as "0–20–40–60–80–100" and should have been "0–50–100–150".
CRIS-Team Scopus Importer:2024-10-18

Correlated Changes Between Volcanic Structures and Magma Composition in the Faial Volcanic System, Azores - Romer, René; Beier, Christoph; Haase, Karsten; Huebscher, Christian (Frontiers in Earth Science, 2018)
The interaction between magmatic and tectonic processes in ocean intraplate volcanism yields insights into the ascent and transport of magmas. Many oceanic intraplate studies lack a temporal component and do not consider changes in tectonic regime and/or magmatic processes during the evolution of magmatic systems. The eastern part of the Azores archipelago formed under the influence of both an intraplate melting anomaly and a system of ultraslow spreading rift axes. The majority of recent submarine and subaerial eruptions in the Azores occur along volcanic rift zones and thus melt transport and volcanic processes are largely controlled by tectonic processes, and are therefore ideally suited to study volcano-tectonic interactions. Here, we investigate how variable the magmatic and tectonic processes are in space and time and how they interact. We present new bathymetric, geophysical, geochemical, and Sr-Nd-Pb isotope data from Faial Island and the surrounding seafloor, providing insights into the interaction between the asthenospheric melting anomaly and extensional lithospheric stresses. The bathymetry reveals large submarine volcanic rift zones on the western flank of Faial, including that of the 1957-1958 Capelinhos eruption. Based on absolute ages and seismic imagery, we develop a relative chronology of the magmatic evolution of the submarine rift zones. Their preferred WNW-ESE orientation implies that the stress field has not changed within the last similar to 1 Ma. We can however show that melt productivity progressively decreased with time. Compositionally different magma batches fed distinct volcanic rift zones and edifices, suggesting that changes in the melting regime occur on a small spatial scale and that the distribution of compositionally similar lavas is tectonically controlled. As melt supply decreases, the tectonic influence on volcanism increases with a stronger localisation of melts along tectonically controlled lineaments. The youngest mafic and intermediate melts (<10 ka) on Faial are exclusively erupted along single rift zones and cover a smaller area, whereas the older volcanism was more widespread.
Keywords: oceanic intraplate volcanism; tectonic stress; lithospheric extension; rift zones; melt transport; dyking

Correlation between magnetic fabrics, strain and biotite microstructure with increasing mylonitisation in the pretectonic Wyangala Granite, Australia - Lennox, P. G.; de Wall, Helga; Durney, D. W. (Tectonophysics, 2016)
Keywords: AMS; Biotite microstructure; Granite; Magmatic versus solid-state flow; Strain

Correlation between the adsorption behavior of colloidal polymer particles and the yield stress of fresh cement pastes - Zhang, Chaoyang; Kong, Xiangming; Yu, Jianwei; Jansen, Daniel; Pakusch, Joachim; Wang, Shengxian (Cement and Concrete Research, 2022)
Correlation between adsorption behavior of colloidal polymers on cement grains and yield stress of fresh cement pastes (fcps) is studied using four polymer latexes with varied surface charge density and glass transition temperature (Tg). Adsorption isotherm of the polymers is divided into two stages: before and after adsorption plateau. Higher charge density and lower Tg are beneficial to adsorption of polymer on cement grains. Before adsorption plateau, the adsorbed polymer particles play a bridging effect among cement grains which firstly increases and then decreases with increasing surface coverage ratio. Maximum bridging effect occurs at surface coverage ratio of ca. 20%. After adsorption plateau, yield stress of the fcps is significantly lower than that of the blank fcp because the adsorbed polymer layer reduces interaction force between cement grains, by increasing the minimum distance between two cement grains and generating repulsive force due to negative charges of the polymer particles.
CRIS-Team Scopus Importer:2021-11-26
Keywords: Adsorption behavior; Colloidal polymers; Fresh cement paste; Yield stress

Correlative Evidences of Monsoon Variability, Vegetation Change and Human Inhabitation in Sanai lake deposit: Ganga Plain, India. - Joachimski, Michael; et al. (Current Science, 2006)
Lake-fill deposits spanning the last 15,000 years provide the first dated record of changes in vegetation, human inhabitation and monsoon variability during the latest Pleistocene-Holocene in the Ganga Plain. The lake vegetation, pollen of plants cultured by man, carbon isotopes and lithology exhibit marked changes with changing monsoon rainfall. A relatively dry spell for 15,000-13,000 14C yrs BP humid conditions from 13,000 to 5800 14C yrs BP and again dry conditions from 5000 to 2000 14C yrs BP are identified. From ∼ 1700 14C yr BP, there is evidence of climatic amelioration. A prominent dry spell corresponding to the Younger Dryas event is identified around an estimated age of 11,500-10,500 14C yrs BP and is accompanied by evidences of decreased human activity during this phase.
UnivIS-Import:2015-03-09:Pub.2006.nat.dgeo.IGM.LG.correl
Keywords: Ganga Plain; Human inhabitation; Monsoon variability; Sanai lake; Vegetation change

Corrigendum to “Alteration of basaltic glass within the Surtsey hydrothermal system, Iceland – Implication to oceanic crust seawater interaction” [Journal of Volcanology and Geothermal Research 429 (2022) 107581] (Journal of Volcanology and Geothermal Research (2022) 429, (S0377027322001123), (10.1016/j.jvolgeores.2022.107581)) - Prause, Simon; Weisenberger, Tobias B.; Kleine-Marshall, Barbara; Monien, Patrick; Rispoli, Concetta; Stefánsson, Andri (Journal of Volcanology and Geothermal Research, 2024)
The authors regret to report a problem with the original bulk rock mass balance calculations published in their 2022 paper, requiring corrections. The changes affect part of the discussion and the conclusions regarding the mobility of elements (details below) during hydrothermal seawater-tuff interaction at Surtsey volcano. In our original paper, bulk rock mass balance was calculated using a single “unaltered parent” bulk rock composition assumed to be that of scoria erupted from the Surtla vent in late December 1963 during the same eruption phase that deposited the Surtur tephra (Schipper et al., 2015). However, a recent re-evaluation of the existing bulk-rock data in Jackson et al. (2019) by Dr. T.J. Barrett (independent research geochemist, Ontario, Canada) shows that the Surtsey pyroclastic deposit exhibits an igneous fractionation trend. This is expressed as a linear positive correlation between TiO2 and FeOtot concentrations in the samples used in our bulk rock mass balance calculations, which in turn leads to downhole variations in the Al2O3/TiO2 ratios (Fig. 1). Based on previous investigations (Schipper et al., 2015), fractionation is likely driven by the formation of clinopyroxene as well as, to a lesser extent, plagioclase and potentially olivine. The formation of accessory (Fe-)Ti-oxides may also contribute to this process. Observed Al2O3/TiO2 ratios increase between ∼180–100 m depth from bottom to top, reflecting ongoing fractionation under relatively oxidized conditions as the magma became less mafic over time. Above ∼80 m Al2O3/TiO2 ratios decrease as TiO2 and FeO concentrations increase. We suggest that this effect is caused by replenishment as a new pulse of less evolved, more mafic melt enters the conduit and begins to fractionate under reduced conditions. Considering the evidence for fractionation, the use of a single parent composition needs to be corrected. We therefore recalculate the bulk rock mass changes by first estimating the magmatic fractionation trend using the previously considered scoria as well as the three least altered samples from the Surtsey drill cores. The least altered samples are from 37.3 m and 145 m depth in SE-01 and 180.8 m depth in SE-02b. This selection was based on previous petrographic investigations of palagonitization extent and secondary mineral abundance (Prause et al., 2020). Reconstructed altered and precursor compositions for each sample and the corresponding mass changes were calculated following the method introduced by MacLean (1990) and applied to Icelandic altered rocks by Libbey and Williams-Jones (2016). Note that, due to the lack of trace element data for altered bulk rock samples, we used Al2O3 and TiO2 as compatible/immobile and incompatible/immobile elements, respectively (Fig. 2). Following the estimation of individual unaltered precursor compositions for each sample, mass changes were recalculated analogously to our original paper. The new results, summarized in Figures 8_corr, 9_corr, and 10_corr, update those displayed in Figures 8, 9, and 10 and supplementary table A.1 in Prause et al. (2022). Corrections to the text are included below. Revised mass changes were found to be minor for FeOtot and MgO in most samples from the SE-01 and SE-02b drillholes (Fig. 8_corr). Such small changes, which are <5% of the initial concentrations of these elements in the precursor rock in most cases, are likely within the margin of error of the mass balance calculations. In the case of MgO, however, two samples from SE-01, at 157.1 and 171 m depth, provide an exception, having gained between +2.2 to +1.6 wt% MgO. These enrichments are significant, representing gains of +32 and + 23 wt%, respectively, relative to the estimated MgO contents of the precursor. Furthermore, the MgO enrichment in the sample from 157.1 m depth coincides with an unusually high loss of −4.0 wt% CaO. The reason for these compositional anomalies is currently unclear but may be related to the fact that the tuff in SE-01 remained relatively unconsolidated below ∼160 m and recovered material mainly consisted of cuttings. The chemical composition of cuttings may be biased towards the preservation of least altered primary minerals and more resistant alteration minerals, which can obscure the effects of alteration (Fowler and Zierenberg, 2016). The SE-01 sample from 170 m depth also displays enrichment in CaO of +2.5 wt% (Fig. 8_corr). Bulk rock chemical analyses in Jackson et al. (2019) indicate unusually high SO3 content for this sample and petrographic observations by Prause et al. (2020) document an increase of the abundance of anhydrite at this depth in the SE-01 drill core. The mass gains of +2.5 wt% CaO in the sample from 170 m depth is therefore interpreted as being due to the increased formation of anhydrite. Additionally, it is possible that gypsum contributes to CaO gains, as this phase was identified at the bottom of hole SE-02b (Prause et al., 2020). Mass changes for Na2O and K2O are variable but generally small with no discernible vertical trends (Fig. 8_corr). Those samples with higher mass gains of Na2O as well as higher losses of CaO and SiO2 are considered to reflect local mineralogical reactions, e.g., palagonitization of basalt glass and plagioclase dissolution (Prause et al., 2020) combined with the formation of analcime in the seawater-saturated part of the hydrothermal system (below 55 m depth). The inferred immobility of Al2O3 on the bulk rock scale changes our previous assessment regarding the Surtsey hydrothermal system acting as an Al source for seawater (Figs. 8-10_corr). Rather, a more likely interpretation is that Al2O3 is mobilized on a small scale (possibly millimetres) during palagonitization before being quickly incorporated into zeolites, Al-tobermorite, and clay minerals. This revised interpretation of the data is more in line with previous assessments of Al solubility and mass fluxes in comparable hydrothermal systems (Barrett et al., 1991, 2005; Barrett and MacLean, 1994; MacLean and Barrett, 1993). The authors would like to apologise for any inconvenience caused. 5.3 Overall mass movement and elemental fluxes in the hydrothermal system at Surtsey (…) Our bulk rock mass balance calculation indicates that the mass changes in most elements are too small to be related to specific alteration processes. However, some sections of the altered tuff below sea level between ∼55–180 m depth have lost up to −3.4 wt% SiO2 and − 1.6 wt% CaO and gained up to +1.8 wt% Na2O. (…) Negative mass changes for SiO2 and CaO were generally highest between ∼80 and 120 m depth. (…) Overall, combined bulk rock and fluid data at Surtsey volcano suggest that 50+ years of submarine water-rock interaction at drillhole depths of up to 180 m has transferred up to 1.24·10−2 mol kg−1 yr−1 Ca and 1.68·10−2 mol kg−1 yr−1 Si from rocks to porewaters, while removing up to 1.17·10−2 mol kg−1 yr−1 Na from porewaters. (…) These findings suggest that, at least in the shallower portion of the volcanic pile, low-temperature hydrothermal alteration of basaltic tuff at Surtsey acts as a source for seawater Ca and Si, but a sink for seawater Na. (…) 6. Conclusions (…) Bulk rock elemental fluxes resulting from water-rock interaction indicate minor losses of SiO2 and CaO to porewaters as well as minor uptake of Na2O. Sodium gains notably become evident below sea level, likely because of interaction of Na-rich seawater with the basaltic tuffs, leading to the formation of zeolites, in particular analcime. Mass changes of SiO2 are generally greater in samples from the 2017 drill core, SE-02b, compared to those from the 1979 drill core, SE-01, indicating continued release of silica to seawater. Mass changes of FeOtot, MgO, and K2O are too small relative to their initial concentrations to accurately assess the fluxes of these elements.[Formula presented] Fig. 1 Downhole changes in bulk rock Al2O3/TiO2 and linear positive correlation between TiO2 and FeOtot (data from Jackson et al., 2019). The TiO2-FeOtot correlation indicates that magmatic fractionation has affected the sample suite; the variation in TiO2 content from sample to sample produces variations in the downhole Al2O3/TiO2 ratio.[Formula presented] Fig. 2 Altered sample compositions and estimated primary fractionation trends (black lines) based on least altered samples. Data from Jackson et al. (2019) and Schipper et al. (2015). Immobile elements: Al2O3 (compatible) and TiO2 (incompatible).[Formula presented] Fig. 8_corr. Updated bulk rock mass balance results for individual mobile elements. Negative values denote a loss from the rock to the hydrothermal solution while positive values indicate rock gains. This figure replaces the original fig. 8 in Prause et al. (2022).[Formula presented] Fig. 9_corr. Updated annual molar flux estimates. This figure replaces the original fig. 9 in Prause et al. (2022).[Formula presented] Fig. 10_corr. Summary of results including updated overview of bulk rock alteration effects. This figure replaces the original fig. 10 in Prause et al. (2022).
CRIS-Team Scopus Importer:2024-07-19

Corrigendum to 'A review of methods used for equilibrium isotope fractionation investigations between dissolved inorganic carbon and CO2' [Earth Sci. Rev. 115(2012), [192-199], doi:10.1016/j.earscirev.2012.08.004.] - Myrttinen, Anssi; Becker, Veith; Barth, Johannes (Earth-Science Reviews, 2015)

Corrigendum to “Disequilibrium compaction overpressure in shales of the Bavarian Foreland Molasse Basin: Results and geographical distribution from velocity-based analyses” [Mar. Pet. Geol. 92 (2018) 37–50](S0264817218300618)(10.1016/j.marpetgeo.2018.02.017) - Drews, Michael; Bauer, Wolfgang; Caracciolo, Luca; Stollhofen, Harald (Marine and Petroleum Geology, 2019)
The authors regret that the following mistakes in the description and graphical representation of the normal compaction trend (NCT) have been erroneously carried forward by the authors from an earlier version of the manuscript to the final version of the manuscript, which does not allow for reproduction of the normal compaction trend used in the study: 1. For all pressure analyses conducted in the study, the constant exponent n of equation (3) has been set to 2.0, instead of 2.19. Therefore, paragraph 1 on page 41 should be read as “[…] which we set to a value of 2.0 for shale, similar to Issler (1992).”2. The vertical stress, necessary to calculate the NCT as represented in Figs. 4, 5 and 6, has been erroneously calculated with a phi0-parameter of 0.35 instead of 0.3 (compare equation (2) and table 1). For the three green data points (Oligocene Normal Pressure, NW-Molasse) of Fig. 5 we spotted an additional minor error in the calculation routine of the vertical effective stress. We attached the corrected figures to the end of this corrigendum.We would like to emphasize that the errors have not been carried forward in the remainder of the study and manuscript. The corrections are only necessary to being able to reproduce the used normal compaction trend, but do not affect any of the results, conclusions or any other figures or written passages of the manuscript. The authors would like to apologize for any inconvenience caused. [Figure presented] Fig. 4. Shale velocities vs. true vertical depth (TVD) for normally pressured Oligocene (yellow and green dots) and Mesozoic shales (blue dots). Oligocene shales from wells in the north-western Bavarian Foreland Molasse Basin (wells marked by green dotted envelope on the map inset and green dots on the velocity-depth plot) generally have faster velocities, which might be attributed to more heterolithic sequences and/or increased uplift. The calculated normal compaction trend (NCT) derived from the combination of the modified Athy equation and the porosity-velocity transform of Raiga-Clemenceau et al. (1988) is represented by the black dashed line. [Figure presented] Fig. 5. Vertical effective stress vs. shale velocity relationship from both normally pressured and overpressured wells. Vertical effective stress values have been derived from drill stem and production tests and wireline formation pressure tests and associated shale velocities are captured from sonic and VSP data from adjacent shale sequences. The dashed black curve represents the normal compaction trend (NCT) established for the Bavarian Foreland Molasse Basin. [Figure presented] Fig. 6. Shale velocities compiled from seismic (VSP) and sonic velocities vs. true vertical depth (TVD) for both normally pressured and overpressured Oligocene and Mesozoic (Cretaceous and Jurassic) shales. Velocities from overpressured Oligocene and Cretaceous shales clearly depart from the normal compaction trend around 2500 m, with some minor diversions even in shallower sections.
CRIS-Team Scopus Importer:2019-12-03

Corrigendum to “Dynamics of dissolved organic carbon in hillslope discharge: Modeling and challenges” (Journal of Hydrology (2017) 546 (309–325), (S0022169416308526), (10.1016/j.jhydrol.2016.12.054)) - Dusek, Jaromir; Vogel, Tomas; Dohnal, Michal; Barth, Johannes; Sanda, Martin; Marx, Anne; Jankovec, Jakub (Journal of Hydrology, 2019)
The authors regret that an error has occurred in the above cited manuscript. The following correction needs to be made: The annual hillslope export of dissolved organic carbon (DOC) in stormflow was smaller than reported by Dusek et al. (2017). While the correct values of the cumulative DOC mass flux were given in Table 3 of the manuscript, they were wrongly converted to per-meter-square exports of DOC, leading to unrealistically high values of DOC export associated with the preferential stormflow (134.8 g C m−2 y−1 in section 4.9 and >100 g C m−2 y−1 in section 5 of the manuscript). The correct values of DOC export associated with preferential stormflow and deep bedrock percolation were 6.1 g C m−2 y−1 and 1.2 g C m−2 y−1, respectively (based on the best behavioral simulation of two growing and two winter seasons). Thus, the predicted DOC export in our study was in the lower range of the values (2–69 g C m−2 y−1) reported by Neff and Asner (2001), who performed field studies in wetland and peatland ecosystems under humid climate. Under conditions of temperate European forest, Kindler et al. (2011) reported mean export of DOC from subsoil of 3.5 ± 1.3 g C m−2 y−1. However, our corrected results still indicate that the contribution of the hillslope DOC export was higher than the amounts reported in the literature under similar geographic conditions. The authors regretfully apologize for any inconvenience caused.
CRIS-Team Scopus Importer:2019-07-09

Corrigendum to “Influence of silica fume addition and content on the early hydration of calcium aluminate cement — The role of soluble silicon” [Cem. Concr. Res. 184 (2024) 107618] (Cement and Concrete Research (2024) 184, (S0008884624001996), (10.1016/j.cemconres.2024.107618)) - Schramm, Tillmann; Neubauer, Jürgen; Götz-Neunhoeffer, Friedlinde (Cement and Concrete Research, 2025)
The authors regret a calculation error regarding the dilution factor which affects the absolute ion concentration values stated in the above paper and therefore also the corresponding calculated saturation indices. All stated concentration values (text and figures) need to be multiplied by a factor of 2.25. However, the authors would like to highlight that this does not affect any statements or conclusions made throughout evaluation and discussion of the data since it was focused on the qualitative evolution and comparison of the mixes. All affected figures were updated and are provided below (Figs. 8–12), including the recalculated saturation indices with the corrected concentrations (Fig. 9). For any sections in the text, it is referred to the correction factor of 2.25. The authors would like to apologise for any inconvenience caused.[Figure presented][Figure presented][Figure presented][Figure presented][Figure presented]
CRIS-Team Scopus Importer:2025-01-31

Corrigendum to "Introduction" [Environ. Pollut. 148 (2007) 693-694] (DOI:10.1016/j.envpol.2007.01.043) - Barth, Johannes; Grathwohl, P.; Jones, K. C. (Environmental Pollution (1970), 2008)

Corrigendum to manuscript ”Dynamics of dissolved organic carbon in hillslope discharge: Modeling and challenges” (Journal of Hydrology (2017) 546 (309–325), (S0022169416308526), (10.1016/j.jhydrol.2016.12.054)) - Dusek, Jaromir; Vogel, Tomas; Dohnal, Michal; Barth, Johannes; Sanda, Martin; Marx, Anne; Jankovec, Jakub (Journal of Hydrology, 2019)
The authors regret that an error has occurred in the above cited manuscript. The following correction needs to be made: The annual hillslope export of dissolved organic carbon (DOC) in stormflow was smaller than reported by Dusek et al. (2017). While the correct values of the cumulative DOC mass flux were given in Table 3 of the manuscript, they were wrongly converted to per-meter-square exports of DOC, leading to unrealistically high values of DOC export associated with the preferential stormflow (134.8 g C m –2 y –1 in section 4.9 and > 100 g C m –2 y –1 in section 5 of the manuscript). The correct values of DOC export associated with preferential stormflow and deep bedrock percolation were 6.1 g C m –2 y –1 and 1.2 g C m –2 y –1 , respectively (based on the best behavioral simulation of two growing and two winter seasons). Thus, the predicted DOC export in our study was in the lower range of the values (2–69 g C m –2 y –1 ) reported by Neff and Asner (2001), who performed field studies in wetland and peatland ecosystems under humid climate. Under conditions of temperate European forest, Kindler et al. (2011) reported mean export of DOC from subsoil of 3.5 ± 1.3 g C m –2 y –1 . However, our corrected results still indicate that the contribution of the hillslope DOC export was higher than the amounts reported in the literature under similar geographic conditions. The authors regretfully apologize for any inconvenience caused.
CRIS-Team Scopus Importer:2019-08-20

Corrigendum to: Marine invertebrate migrations trace climate change over 450 million years (Global Ecology and Biogeography, (2018), 27, 6, (704-713), 10.1111/geb.12732) - Reddin, Carl James; Kocsis, Ádám; Kießling, Wolfgang (Global Ecology and Biogeography, 2020)
JUSTIFICATION The original results to Reddin, Kocsis, and Kiessling (2018) included an error in the code that intended to match geographical grid cells between neighbouring ages (“matched-cells” hereafter), via a nonsensical call to the subset() function. After correcting this coding mistake, we checked these results against those acquired with the matched-cells step omitted entirely. The results held only when the matched-cells step was omitted. This invalidated our original belief that matched-cells would help “homogenize geographical sampling coverage between consecutive ages”. The restriction to matched-cells results in a median loss of 23% of survivor species compared to without matched-cells (median = 118 survivor species per age to median = 153 without matched-cells). Additionally, we suspect that the two spatial corrections for sampling variation interfere with one another, that is, the use of (a) matched-cells and (b) subtraction of the sampling focus from the median genus range centre (to calculate the latitudinal deviation). We therefore reproduce the analyses without limiting data to matched-cells and present the updated results, including the five changed results figures, here. In summary, the changes to the results are minor and the scientific conclusions remain as originally stated. UPDATED VERSIONS OF KEY FIGURES All results hold following the omission of the matched-cells step, albeit with slightly weaker strength, with the central correlation decreasing from rho = 0.30 (p =.01) to rho = 0.24 (p =.034; Figure 1). Following the order of presentation in the original paper, the central correlation rises, as before, with (a) hemisphere-switching, but to rho = 0.39 (95% CIs = 0.19–0.56, optimum threshold = 126; Figure 2) instead of the original rho = 0.48 (95% CIs = 0.29–0.64, optimum threshold = 108 genera). The central correlation for the Southern Hemisphere remained insignificant (rho = 0.08, p =.6). If (b) the median latitudinal deviation was supplemented with the 0.2-quantile latitudinal deviation, when the Northern Hemisphere median occurrence palaeolatitude vacated the tropics, a substantial improvement to the central correlation is no longer observed (small increase to Rho = 0.26, 95% CIs = 0.04–0.46, rather than the original increase to rho = 0.40, 95% Cis = 0.19–0.57; see next paragraph). However, as in the original version, combining both hemisphere-switching and integrating the 0.2-quantile deviation (steps a and b), raised the central correlation to rho = 0.35 (95% CIs = 0.14–0.53), but did not improve upon using hemisphere-switching alone. (c) Weighting the correlation from the hemisphere-switching approach by the age inverse extinction rate resulted in the highest correlation strength, at rho = 0.41 (95% CIs = 0.2–0.58; Figure 3) instead of the original rho = 0.56 (95% Cis = 0.39–0.70). 1 Figure (Figure presented.) Latitudinal range shifts of Northern Hemisphere marine genera (black lines) are correlated with low latitude mean shallow seawater temperature (red lines, right-hand y axis). Temperature calculated from fossil shell oxygen isotopes following Veizer and Prokoph (2015). Grey shading around the thick black line shows bootstrapped 95% confidence intervals. For both variables, thick lines show a moving window of three consecutive bins. Thin lines show the unsmoothed bin-to-bin changes. This is the updated original Figure 2. Contributing genera median range centre = 23.6°. There is now no gap in the latitudinal deviation time series for the Northern Hemisphere. Latitudinal deviation mean is 0.60° (absolute mean = 1.93°). Geological periods are lightly shaded and abbreviated as O = Ordovician; S = Silurian; D = Devonian; C = Carboniferous; P = Permian; Tr = Triassic; J = Jurassic; K = Cretaceous; Pg = Palaeogene; N = Neogene 2 Figure (Figure presented.) The effect of changing a threshold minimum number of genera in “hemisphere switching” on the correlation of latitudinal deviation with climate. When the minimum threshold is reached, latitudinal deviations are sourced from the opposite hemisphere. Dotted lines show the correlation without any hemisphere switching, for northern and southern palaeo-hemispheres separately. Filled circles are p <.05. Serial autocorrelation in times series removed by generalized differencing. This is the updated original Figure 3. Optimum threshold of sampled genera = 126 3 Figure (Figure presented.) Time series of latitudinal range shifts of marine genera (black lines) improved by hemisphere switching alongside low latitude shallow seawater temperature (red lines, right-hand y axis). Details as in Figure 1. This is the updated original Figure 4. Contributing genera median range centre = 27.6°. Latitudinal deviation mean is 0.38° (absolute mean = 1.89°). All other descriptions as in Figure 1. O = Ordovician; S = Silurian; D = Devonian; C = Carboniferous; P = Permian; Tr = Triassic; J = Jurassic; K = Cretaceous; Pg = Palaeogene; N = Neogene The latitudinal deviation quantiles still show an increase in strength of relationship with climate from higher to lower quantiles (Figure 4, rho = −0.58, n = 9, p =.11; down from the original rho = –0.78, n = 9, p =.02), but the trend is only significant when the sampling focus vacated the tropics, approximately after the Carnian age (rho = −0.83, n = 9, p =.008; Figure 4; also see original Figure 1 at 230 myr). This is presumably because the highest and lowest quantiles are more affected by noise and only become useful when the median sampling focus is no longer opportunely positioned, that is, when the sampling centre vacates the tropics. Prior to the Norian age (Triassic), the correlation between latitudinal deviation and climate with hemisphere switching (i.e. step (a), above) is significant even without smoothing (rho = 0.34, 95% Cis = 0.04–0.58, ages n = 43). The slopes of warm and cool ages remain significantly different to each other (Z-statistic = −3.23, p =.0006; Figure 5). 4 Figure (Figure presented.) Correlation strength between shallow seawater temperature and genus latitudinal range shifts decreases from more equatorward (0.1-quantile, median palaeolatitude = 12.7°) to poleward genera (0.9-quantile, median palaeolatitude = 39.0°; quantile steps of 0.1). Solid symbols show Spearman's rho coefficients that 95% confidence intervals (dashed lines) overlap zero. Serial autocorrelation in times series removed by generalized differencing. This is the updated original Figure 5. The latitudinal means for the coloured lines are the mean sampling latitudes. The strongest correlation over all ages is with the 0.5-quantile (i.e. median, given in main text) but when the quantile time series are split, the post-Carnian 0.2-quantile has the strongest correlation (rho = 0.35, p =.036) 5 Figure (Figure presented.) Poleward migrations are more likely to be recorded by lower latitude sampling foci, (a) especially during warm ages (red line and points, age seawater temperature > Phanerozoic mean, slope = −0.20, p =.0005, n = 33). Each point represents one geological age. Blue line and points represent cool ages (age seawater temperature < Phanerozoic mean, slope = −0.02, n.s., n = 45). (b) Termplots of the independent effects of the predictor variables in a multiple regression including both temperature and sampling latitude as predictor variables for latitudinal deviations. Points are the partial residuals. This is the updated original Figure 6 The interpretation of these results is unchanged. Thanks are owed to Gwen S. Antell for noticing this error. The code was updated in the Dryad repository on January 10, 2020. The authors apologise for this error.
CRIS-Team Scopus Importer:2020-06-23

C–O stable isotope geochemistry of carbonate minerals in the nonsulfide zinc deposits of the middle east: A review - Mondillo, Nicola; Boni, Maria; Joachimski, Michael; Santoro, L (Minerals, 2017)
Keywords: C–O stable isotopes; Middle East; Weathering; Zn-nonsulfide deposits

C-O stable isotopes geochemistry of Tunisian nonsulfide zinc deposits: A first look - Garnit, Hechmi; Boni, Maria; Buongiovanni, Giuliana; Arfè, Giuseppe; Mondillo, Nicola; Bouhlel, Salah; Balassone, Giuseppina; Joachimski, Michael (Minerals, 2018)
Keywords: C-O stable isotopes; Mineralogy; Nonsulfide deposits; Paleoclimate; Tunisia

Costinuculana magharensis n. gen. n. sp (Bivalvia, Nuculanidae) from the Middle Jurassic of Gebel Maghara, North Sinai, Egypt - Ayoub-Hannaa, Wagih; Abdelhady, Ahmed Awad; Fürsich, Franz (Journal of Paleontology, 2017)
<div class="row" style="box-sizing: border-box; margin: 0px -0.64286rem; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: "Noto Sans", Helvetica, Roboto, Arial, sans-serif; font-size: 16px; vertical-align: baseline; max-width: none; width: auto; color: rgb(51, 51, 51);"> <div class="large-10 medium-10 small-12 columns" style="box-sizing: border-box; margin: 0px; padding: 0px 0.64286rem; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; width: 742.125px; float: left; position: relative;"> <div class="description" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: 13px; vertical-align: baseline; -webkit-font-smoothing: antialiased; color: rgb(89, 89, 89); line-height: 1.6em !important;"> <div class="abstract" data-abstract-type="normal" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;"> <p style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-stretch: inherit; line-height: 1.6; font-family: inherit; font-size: 1em; vertical-align: baseline; text-rendering: optimizeLegibility;"> The nuculanid bivalve <span class="italic" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: italic; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;">Costinuculana magharensis new genus new species is described from the middle to upper Bathonian Kehailia Formation of Gebel Maghara, North Sinai, Egypt. <span class="italic" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: italic; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;">Costinuculana differs from other genera of the family Nuculanidae by the presence of opisthocline ribs along the rostrum. These ribs are variable in shape and size, straight to folded posteriorly, bifurcate ventrally and occasionally postero-dorsally, and cover an area <span class="italic" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: italic; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;"> 45% of the total valve length from the posterior end. The life position of <span class="italic" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: italic; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;">C. <span class="italic" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: italic; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;">magharensis n. gen. n. sp. is reconstructed on the basis of a functional interpretation of its morphology and by comparison with closely related Recent forms. The asymmetrical commarginal ribs facilitated the burrowing process. The posterior oblique ribs are asymmetrical in cross-section with a steeply concave side in the burrowing direction and slightly convex side in the opposite direction. They probably kept the bivalve in a stable position once the desired depth had been reached. The thick oblique ribs probably also increased the strength of the rostrum and offered resistance against durophagous predators, being presumably partly exposed above the sediment-water interface. Based on the associated fauna, <span class="italic" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-style: italic; font-variant: inherit; font-weight: inherit; font-stretch: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;">Costinuculana n. gen. lived in a low-energy environment characterized by a fine-grained, soft substrate.
UnivIS-Import:2017-12-18:Pub.2017.nat.dgeo.IGM.LP.costin
Keywords: new genus; new species; Bivalvia; Nuculanidae; Costinuculana magharensis; Bathonian Kehailia Formation; Gebel Maghara; Egypt; Middle Jurassic

Cosubstitution of Zinc and Strontium in ß-Tricalcium Phosphate: Synthesis an Characterization - Kannan, Sanjeevi; Götz-Neunhoeffer, Friedlinde; Neubauer, Jürgen; da Fonte Ferreira, José Maria (Journal of the American Ceramic Society, 2011)
UnivIS-Import:2015-03-09:Pub.2011.nat.dgeo.IGM.LM.cosubs

Coupling of geographic range and provincialism in Cambrian marine invertebrates - Na, Lin; Kocsis, Ádám; Li, Qijian; Kießling, Wolfgang (Paleobiology, 2022)
The Cambrian saw a dramatic increase in metazoan diversity and abundance. Between-assemblage diversity (beta diversity) soared in the first three Cambrian stages, suggesting a rapid increase in the geodisparity of marine animals during the Cambrian radiation. However, it remains unclear how these changes scale up to first-order biogeographic patterns. Here we outline time-traceable provinces for marine invertebrates across the Cambrian period using a compositional network based on species-level fossil occurrence data. Results confirm an increase in regional differences of faunal composition and a decrease in by-species geographic distribution during the first three stages. We also show that general biogeography tends to be reshaped after global extinction pulses. We suggest that the abrupt biogeographic differentiation during the Cambrian radiation was controlled by a combination of tectonics, paleoclimate, and dispersal capacity changes.
CRIS-Team WoS Importer:2022-12-30

Crack growth rates in lithium disilicates with bulk (mis)alignment of the Li2Si2O5 phase in the [001] direction - Kirsten, Julia; Belli, Renan; Wendler, Michael; Petschelt, Anselm; Hurle, Katrin; Lohbauer, Ulrich (Journal of Non-Crystalline Solids, 2020)
Processing-induced alignment of Li2Si2O5 crystals in biomedical lithium disilicate glass-ceramics have been shown to increase the monotonic resistance to fracture and better simulate the mechanical behavior of natural dental tissues. The (mis)orientation of the [001] direction in the Li2Si2O5 crystal phase relative to the crack growth plane was induced by injection-molding of a high aspect ratio composition in order to determine the effect of crystal alignment. The role of particulate geometry was assessed by comparing two compositions having randomly oriented Li2Si2O5 crystals of similar phase fraction but dissimilar crystal aspect ratios. Static and cyclic fatigue experiments in varying frequencies and R-ratios were conducted to clarify the degradation of crack bridging mechanisms induced by the crystal phase during repetitive opening and closure of the crack faces. Both crystal alignment and aspect ratio showed to play important roles in affecting the subcritical crack growth resistance the lifetime of lithium disilicate biomedical components.
CRIS-Team Scopus Importer:2020-02-14
Keywords: Anisotropy; Crystal alignment; Cyclic fatigue; Lithium disilicate; Static fatigue

Crack-healing during two-stage crystallization of biomedical lithium (di)silicate glass-ceramics - Belli, Renan; Lohbauer, Ulrich; Götz-Neunhoeffer, Friedlinde; Hurle, Katrin (Dental Materials, 2019)
Objective: The study is aimed to evaluate the two single commercially available two-step lithium-(di)silicate systems by analyzing their parent glass composition and studying the quantitative crystalline and glass phase evolution during the second stage heat-treatment. The mechanical repercussions of the crystallization firing were evaluated using strength and fracture toughness tests. Methods: XRF and ICP-OES were used to determine the oxide composition of the parent glasses in Suprinity PC (Vita Zahnfabrik) and IPS e.max CAD (Ivoclar-Vivadent). The crystalline phase of both materials was determined by quantitative XRD and the G-factor method in the partially and post-crystallization states. The oxide composition of the residual glass phase was derived by subtracting the chemistry of the crystalline phase fractions from the parent glass composition. Mechanical testing of biaxial flexural strength and fracture toughness were used to demonstrate how crack-like defects behave during crystallization. Results: The two tested lithium (di)silicate systems showed strong differences in oxide composition of the parent glass. This showed to influence the transformation of lithium metasilicate in lithium disilicate, with the former remaining in high vol.% fraction in the post-crystallization Suprinity PC. In IPS e.max CAD cristobalite precipitated at the surface during the second-heat treatment. Strength and fracture toughness tests revealed that crack in both materials, whether introduced by grinding or indentation, heal during the crystallization firing. Cristobalite seemed to have contributed to a surface strengthening effect in IPS e.max CAD. Significance: Accurate crystalline phase quantification aids in the determination of the residual glass composition in dental glass-ceramics. For both systems crystallization firing induced healing of cracks generated by CAM grinding.
CRIS-Team Scopus Importer:2019-05-28
Keywords: Dental; Fracture toughness; Glass-ceramic; Lithium disilicate; Lithium silicate; X-ray diffraction

Cretaceous seawater and hydrothermal fluid compositions recorded in abiogenic carbonates from the Troodos Ophiolite, Cyprus - Weinzierl, Christoph; Regelous, Marcel; Haase, Karsten; Bach, W.; Böhm, F.; Garbe-Schönberg, D.; Sun, Yadong; Joachimski, Michael; Krumm, Stefan (Chemical Geology, 2018)
Keywords: 87Sr/86Sr; Akaki; Carbonates; CO2; Alteration; Calcites; Hydrothermal fluid; Mg/Ca; Cretaceous; Fluid evolution; Seawater composition; Seawater; oxygen isotopes; Ophiolite; Troodos; Thermodynamic model; Sr/Ca; Seawater-rock reaction; δ44/40Ca

Crustal Contamination of the Mantle-Derived Liuyuan Basalts: Implications for the Permian Evolution of the Southern Central Asian Orogenic Belt - Yu, Yuanyang; Zong, Keqing; Yuan, Yu; Klemd, Reiner; Wang, Xin Shui; Guo, Jingliang; Xu, Rong; Hu, Zhaochu; Liu, Yongsheng (Journal of Earth Science, 2022)
The Permian basalts in the Central Asian Orogenic Belt (CAOB) are crucial for constraining the closure of the Paleo-Asian Ocean. However, the origin of these basalts is still under discussion. Here, we present comprehensive bulk-rock geochemical, Sr−Nd−Pb−Hf isotopic, and zircon U−Pb−Lu−Hf isotopic data of the Liuyuan basalts and coexisting gabbros, which are located in the Beishan Orogen in the southern CAOB, to constrain their emplacement setting and tectonic implications. Our new gabbro ages of ca. 288–294 Ma are interpreted to represent the formation time of the Liuyuan basaltic belt. The Liuyuan basalts show MORB-like rare earth element (REE) patterns and bulk-rock εHr(t) and εNd(t) values of 11.0–15.4 and 4.6–9.2, respectively, suggesting an origination mainly from a depleted mantle source. However, positive Pb anomalies, Nb−Ta depletions, and high Th/Yb ratios as well as evolved Sr−Nd−Pb−Hf isotopic compositions of some samples indicate variable continental crustal contribution. According to the covariation of Pb anomalies (Pb* =2×PbN/(CeN+PrN)) with Sr−Nd−Pb−Hf isotopic compositions, we speculate that parent magma of the Liuyuan basalt was contaminated by continental crustal materials during the eruption rather than having been generated from an enriched mantle source. As revealed by mixing modelling, the Liuyuan basaltic magmas would require a minor (<10%) upper continental crustal assimilation to explain the enriched trace elemental and radiogenic Sr−Nd−Pb−Hf isotopic signatures. Consequently, the Liuyuan basaltic belt is believed to have been generated in a continental extensional environment instead of an oceanic setting and does not constitute a Permian ophiolitic suture zone as previously suggested, since the Paleo-Asian Ocean was already closed in the southern Beishan Orogen in the Early Permian.
CRIS-Team Scopus Importer:2022-10-28
Keywords: Beishan Orogen; Central Asian Orogenic Belt; crustal contamination; Liuyuan basaltic belt; Pb anomaly; tectonics

Crustose coralline red algae frameworks and rhodoliths: Past and present - Rebelo, Ana Cristina; Teichert, Sebastian; Bracchi, Valentina A.; Rasser, Michael W.; Basso, Daniela (2022)

Cryogenian transpression and granite intrusion along the western margin of Rodinia (Mt. Abu region): Magnetic fabric and geochemical inferences on Neoproterozoic geodynamics of the NW Indian block - de Wall, Helga; Pandit, Manoj K.; Dotzler, Ramona; Just, Jana (Tectonophysics, 2012)
Keywords: Anisotropy of magnetic susceptibility; Cryogenian transpression; Geochemistry; Malani Igneous Suite; NW India

Cryptic biostalactites in a submerged karst cave of the Belize Barrier Reef revisited: Pendant bioconstructions cemented by microbial micrite - Gischler, Eberhard; Heindel, Katrin; Birgel, Daniel; Brunner, Benjamin; Reitner, Joachim; Peckmann, Jörn (Palaeogeography, Palaeoclimatology, Palaeoecology, 2017)
Microbial carbonates are important components of postglacial tropical coral reef frameworks. Curious calcium carbonate protrusions in a submarine karst cave in the Belize Barrier Reef platform were initially interpreted as being largely the product of physicochemical precipitation around a meshwork of serpulid tubes. New petrographical, mineralogical, geochronological, and inorganic and organic geochemical data suggest that sulfate-reducing bacteria played a substantial role in carbonate formation, just as in cryptic settings of other modern, tropical coralgal reefs. The bacterial involvement in carbonate authigenesis is indicated by the content and isotopic composition of carbonate-associated sulfate, the presence of non-isoprenoidal sn-1-mono-O-alkyl glycerol monoethers (MAGEs) and terminally-branched fatty acids, and the observation that the majority of molecular fossils assigned to sulfate-reducing bacteria are tightly associated with the carbonate mineral lattice. The carbonate protrusions that were formerly named pseudostalactites, are termed biostalactites here to underline the significance of biological activity during carbonate formation. The Belize biostalactites are composed of four carbonate phases including serpulid tubes, lithified sediment, and microbial carbonate, as well as unconsolidated sediment usually found in macroborings of bivalve molluscs. Lithified sediment and microbial carbonate are fine-grained with clotted, mottled, and peloidal textures. While serpulid tubes are aragonitic, lithified sediment and microbial carbonates are mixtures of high-magnesium calcite and aragonite. Magnesium-calcite content increases with increasing consolidation. Lithified sediment and microbial carbonate are interpreted as fine, biodetrital sediment that was subsequently cemented by authigenic micrite. Scalenohedral high-magnesium calcite and acicular aragonite cements played a subordinate role in cementation. Carbon and oxygen stable isotope ratios of lithified sediment and microbial carbonate exhibit similar ranges as modern reefal microbialites. Our study exemplifies that heterotrophic bacteria can be a crucial agent that contributes to the formation of carbonate build-ups by cementing skeletal frameworks in cryptic environments.
UnivIS-Import:2017-12-18:Pub.2017.nat.dgeo.IGM.LP.crypti
Keywords: Carbonate; Holocene; Microbialite; Reef; Sulfate reduction

Cryptic diversity along the onshore-offshore gradient: marginal marine environments were a cradle of early vertebrates - Jarochowska, Emilia; Viira, Viive; Einasto, Rein; Nawrot, Rafał; Bremer, Oskar; Männik, Peep; Munnecke, Axel (Macroecology 2019 - Bridging local patterns and global challenges, 2019)

Cryptic fabrics in epiclastics of the Sindreth Group: evidence for late- Neoproterozoic deformation in the western foreland of the Delhi Fold Belt, NW-India. - de Wall, Helga; et al. (Beringeria, 2007)
UnivIS-Import:2015-03-09:Pub.2007.nat.dgeo.IGM.c3tekt.crypti

Crystal chemistry and crystal structures of complex hexa-aluminates and hexa-ferrites - Göbbels, Matthias (2004)
UnivIS-Import:2015-03-09:Pub.2004.nat.dgeo.IGM.LM.crysta

Crystallization study of sol–gel derived 13-93 bioactive glass powder - Nawaz, Qaisar; de Pablos-Martín, Araceli; Martins de Souza e Silva, Juliana; Berthold, Lutz; Hurle, Katrin; Contreras Jaimes, Altair T.; Sitarz, Maciej; Brauer, Delia S.; Boccaccini, Aldo R. (Journal of the European Ceramic Society, 2020)
Multicomponent silicate bioactive glass (BG) (53SiO2‐20CaO‐6Na2O‐4P2O5‐12K2O‐ 5MgO in wt. %) (13–93 composition) was prepared via the sol–gel process. The influence of thermal treatment on the crystallization was evaluated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray nano-computed tomography (nano-CT). The temperature and time of the thermal treatment strongly influenced the formation of the crystalline phases. The preliminary outcomes demonstrate the possibility of tailoring the crystallinity of 13–93 BG powder in the range 5–43 wt. % by controlling the temperature and time of the heat treatment. The microstructure of powders sintered at two different temperatures (650 °C and 700 °C from 30 min to 4 h) was evaluated by TEM. X-ray nano-computed tomography (nano-CT) was used to visualize the 3D morphology and distribution of crystallization areas in the samples in powder form. A large range between the glass transformation and the crystallization temperatures is observed, which provides the prospect of a suitable material to manufacture directly 3D structures (e.g. porous scaffolds) without an intermediate processing step.
CRIS-Team Scopus Importer:2020-10-16
Keywords: Bioactive glasses; Crystallization behavior; Rietveld refinement; Sintering of 13-93 bioactive glass; Sol–gel

Crystallographic control and texture inheritance during mylonitization of coarse grained quartz veins - Ceccato, Alberto; Pennacchioni, Giorgio; Menegon, Luca; Bestmann, Michel (Lithos, 2017)
Keywords: Quartz deformation; Crystallographic preferred orientation (CPO); EBSD; Dynamic recrystallization

Crystal structure of the new magnetoplumbite related compound in the system SrO Al_2_O_3_-MgO - Iyi, Nobou; Göbbels, Matthias (Journal of Solid State Chemistry, 1996)
A new phase in the system SrO–Al2O3–MgO, which was analyzed by EPMA as Sr2MgAl22O36, was recently found. It is located in the middle of the join connecting strontium hexaaluminate (SrAl12O19) of magnetoplumbite structure and strontium magnesium hexaaluminate (SrMgAl10O17) of β-alumina structure. The crystals were grown by the floating zone method and its crystal structure was analyzed by using the single crystal X-ray was analyzed by using the single crystal X-ray diffraction method. The space group wasP<img alt="Full-size image (<1 K)" class="imgLazyJSB inlineImage" data-inlimgeid="1-s2.0-S0022459696900808-si1.gif" data-loaded="true" height="15" src="http://ars.els-cdn.com/content/image/1-s2.0-S0022459696900808-si1.gif" style="margin-top: -5px; vertical-align: middle; display: inline;" title="Full-size image (<1 K)" width="11" />m2 with lattice parametersa= 5.583 Å andc= 22.225 Å. The observedc-axis length is intermediate between those of SrAl12O19(c= 22.00 Å) and SrMgAl10O17(c= 22.399 Å). The structure refinement result has shown that it had the alternate stacking of the conduction layers of magnetoplumbite-type (SrAlO3) and β-alumina-type (SrO) separated by a spinel block ((Al, Mg)11O16). This is the first time that such a “mixed-layer” structure of β-alumina and magnetoplumbite is found to exist in the hexaaluminates containing one species of large cation.
UnivIS-Import:2015-03-05:Pub.1996.nat.dgeo.IGM.LM.crysta

C-S-H Pore Size Characterization Via a Combined Nuclear Magnetic Resonance (NMR)-Scanning Electron Microscopy (SEM) Surface Relaxivity Calibration - Naber, Christoph; Kleiner, Florian; Becker, Franz; Long Nguyen-Tuan,; Roessler, Christiane; Etzold, Merlin A.; Neubauer, Jürgen (Materials, 2020)
A new method for the nuclear magnetic resonance (NMR) surface relaxivity calibration in hydrated cement samples is proposed. This method relies on a combined analysis of 28-d hydrated tricalcium silicate samples by scanning electron microscopy (SEM) image analysis and H-1-time-domain (TD)-NMR relaxometry. Pore surface and volume data for interhydrate pores are obtained from high resolution SEM images on surfaces obtained by argon broad ion beam sectioning. These data are combined with T-2 relaxation times from H-1-TD-NMR to calculate the systems surface relaxivity according to the fast exchange model of relaxation. This new method is compared to an alternative method that employs sequential drying to calibrate the systems surface relaxivity.
CRIS-Team WoS Importer:2020-05-22

Cu2+ doped β-tricalcium phosphate: Solid solution limit and crystallographic characterization by rietveld refinement - Späth, Karla; Götz-Neunhoeffer, Friedlinde; Hurle, Katrin (Journal of Solid State Chemistry, 2020)
β-tricalcium phosphate (β-TCP) is applied in medicine. As Cu2+ is known to exhibit antimicrobial activity in the body and to improve wound healing and angiogenesis, it is an eligible ion for substitution in β-TCP. Crystalline β-TCP with varying amounts of Cu2+ ranging from 0 to 20 ​mol% was synthesized at 1000 ​± ​10 ​°C and investigated by powder X-ray diffraction followed by Rietveld refinement. The lattice parameters a and c and the unit cell volume of Ca3 - xCux(PO4)2 showed a significant decrease with increasing Cu2+ amount until a content of 15 ​mol% Cu2+. In all samples with Cu2+ amounts higher than 14 ​mol% Ca3Cu3(PO4)4 was detected as secondary phase. The refinement of the occupancy factors showed a preferred incorporation of Cu2+ at the Ca(5) site. The limit of Cu2+ incorporation in the structure of β-TCP before forming a secondary phase can be inferred at a Cu2+ content of 15 ​mol%.
CRIS-Team Scopus Importer:2020-02-18
Keywords: Copper doping; Crystal structure; Substitution limit; Tricalcium phosphate

Culture-Led Urban Development vs. Capital-Led Colonization of Urban Space: Savamala-End of Story? - Jocic, Nikola (Urban Science, 2020)
The city quarter of Savamala, as an integral part of Belgrade, has had a very turbulent development path during the last two centuries. This path included several ups and downs, and culminated in tension over the last decade. Savamala fell into silent oblivion in the 20th century, but succeeded in re-emerging into the focus of the public and interest groups, mainly due to the cultural milieu that developed in this area at the beginning of the 21st century. The cultural vibes of the city quarter attracted various urban actors, who created a new image of Savamala. Eventually, cultural functions started to fade; however, after several years and through vague political decisions, Savamala became the part of the largest construction site in Belgrade, the Belgrade Waterfront. This article highlights the development of Savamala in the 2010s-from a forgotten city quarter to a rising cultural quarter and finally to the 'future centre of the city'. This analysis shows the participation of different stakeholders at different stages of development (their influence, power levels, and the mechanisms they used), as well as the footprints that urban development left in the quarter.
CRIS-Team WoS Importer:2021-03-05

Cumulate olivine: A novel host for heavy rare earth element mineralization - Brandt, Sönke; Faßbender, Marc Lorin; Klemd, Reiner; Macauley, Chandra; Felfer, Peter; Haase, Karsten (Geology, 2020)

Current measures for distance decay in similarity of species composition are influenced by study extent and grain size - Steinbauer, Manuel; Dolos, Klara; Reineking, Björn; Beierkuhnlein, Carl (Global Ecology and Biogeography, 2012)
Aim: The relationship between geographic distance and similarity in species composition is regularly used as a measure of species turnover and beta diversity. Distance–decay analyses are applied, cited and compared despite the variable extent, and different grain sizes of records (e.g. plots, islands, states) are regularly used within such analyses. Currently, differences among distance–decay relationships that cover different grain sizes and extents are attributed to ecological processes that are suspected to operate differently over varying extents and grain sizes. We assess whether the implicit assumption that the distance–decay relation is independent of grain size and study extent is valid, or whether sampling design could be the underlying cause for observed differences. Location: An artificial one-dimensional ‘landscape’. Methods: The distance–decay relationship was quantified in simulated communities. Grain and study extent were varied systematically. In each sampled data set the linear relation of Simpson and Sørensen similarity to geographic distance (on both log-transformed and original scales) between 100 even-sized equidistant plots was assessed using linear regression and generalized linear regression with a log-link function. Regressions were applied either including or removing zero similarities from the data. Results: Both the slope (measuring turnover) and the goodness of fit measure r2 (quantifying the influence of space on species composition) of the distance–decay relationship were strongly influenced by grain and study extent. Approaches that are able to cope with zero similarity values of large distance comparisons were less dependent on grain and extent. Main conclusions: Reported differences between landscapes detected by current distance–decay measures cannot be explicitly traced back to ecological scale-specific processes. Instead, they can largely be attributed to sampling design and are highly sensitive to grain size and study extent. More appropriate approaches for the study of distance–decay and the understanding of scale-specific processes are required.
Keywords: Beta diversity; Biodiversity; Dissimilarity; Ecological gradient; Sørensen similarity; Scale dependence; Simpson similarity; Species turnover

Curtain up - Online is on stage - Kuntz, David; Barth, Johannes (Grundwasser, 2012)

Customizable Induction Heating Profiles: from Tailored Colloidally Stable Nanoparticles Toward Multi-Stage Heatable Supraparticles - Luthardt, Leoni; Raczka, Theodor; Hurle, Katrin; Müssig, Stephan; Mandel, Karl (Advanced Functional Materials, 2024)

d13C chemostratigraphy in Lower-Middle Ordovician succession of Öland (Sweden) and the global significance of the MDICE - Calner, Mikael; Lehnert, Oliver; Wu, Rongchang; Dahlqvist, Peter; Joachimski, Michael (Gff, 2014)
UnivIS-Import:2015-03-09:Pub.2014.nat.dgeo.IGM.LG.d13cch

d13C chemostratigraphy in the upper Tremadocian through lower Katian (Ordovician) carbonate succession of the Siljan district, central Sweden. - Lehnert, Oliver; Meinhold, Guido; Wu, Rongchang; Calner, Mikael; Joachimski, Michael (Estonian Journal of Earth Sciences, 2014)
UnivIS-Import:2015-03-09:Pub.2014.nat.dgeo.IGM.LG.d13cch_3

d18O compostion from conodont apatite indicates climate cooling during the Middle Pridoli - Zigaite, Zivile; Joachimski, Michael; Lehnert, Oliver; Brazauskas, Antanas (Palaeogeography, Palaeoclimatology, Palaeoecology, 2010)
UnivIS-Import:2015-03-09:Pub.2010.nat.dgeo.IGM.LG.d18oco

d18O record from conodont apatite across the Lower-Middle Ordovician boundary on the Yangtze platform (Western Hubei, South China). - Lehnert, Oliver; Stouge, Svend; Joachimski, Michael; Buggisch, Werner (Acta Palaeontologica Sinica, 2007)
UnivIS-Import:2015-03-09:Pub.2007.nat.dgeo.IGM.LG.d18ore

Darriwilian (Middle Ordovician) chemostratigraphy linked to graptolite, conodont and trilobite biostratigraphy in the Fågelsång-3 drill core, Scania, Sweden - Bergström, Stig M.; Ahlberg, Per; Maletz, Jörg; Lundberg, Frans; Joachimski, Michael (GFF, 2018)
Keywords: chemostratigraphy; conodonts; Baltoscandia; biostratigraphy; graptolites; Middle Ordovician

Das Belemnitenschlachtfeld von Mistelgau - Schulbert, Christian (Der Steinkern, 2013)
UnivIS-Import:2015-03-09:Pub.2013.nat.dgeo.IGM.LP.dasbel
Keywords: Belemnitenschlachtfeld; Mistelgau

Das GEO-Zentrum an der KTB: Informations- und Bildungseinrichtung in der Nachfolge eines nationales geowissenschaftlichen Großprojektes - de Wall, Helga; et al. (Geologische Blätter für Nordost-Bayern und angrenzende Gebiete, 2010)
UnivIS-Import:2015-03-09:Pub.2010.nat.dgeo.IGM.c3tekt.dasgeo

Das Hessische Landesmuseum Darmstadt - Geschichte und Neukonzeption - Roden, Vanessa (Conference: Centenary Meeting of the Paläontologische Gesellschaft, 2012)

Das integrierte EU-Projekt AquaTerra erreicht sein zweites Projektjahr - Barth, Johannes; et al. (Grundwasser, 2006)

Das lithostratigraphische Profil der Forschungsbohrung "Münsterappel I". - Haneke, Jost; Stollhofen, Harald (Mainzer Geowissenschaftliche Mitteilungen, 1994)
UnivIS-Import:2015-03-05:Pub.1994.nat.dgeo.IGM.LG.daslit

Das Potenzial coralliner Rotalgen als SST-Proxy und für die Evaluierung globaler Klimamodelle: eine Fallstudie in Neuseeland - Kropac, Elena; Mölg, Thomas; Teichert, Sebastian (Tagungsband zur 39. Sitzung des Arbeitskreises Klima, 2021)
Globale Klimamodelle (General Circulation Models; GCMs) sind das aktuell wichtigste Instrument der Klimawissenschaft, um Aussagen und Projektionen über das Klima der Zukunft zu treffen. Sie liefern zudem Daten-Input für regionale Atmosphärenmodelle, mithilfe derer der sog. „Klima-Impakt“ großräumiger Klimaänderungen auf regionaler und lokaler Ebene berechnet werden kann. Um möglichst akkurate Projektionen und Inputdaten zu gewährleisten, müssen GCMs bestmöglich mit Klimaaufzeichnungen der Vergangenheit evaluiert werden, wobei der Fokus auf der sog. "historischen Periode" von 1850 bis zur Gegenwart liegt. Die Evaluierung ist für den Zeitraum vor 1950, und insbesondere für die Südliche Hemisphäre, aufgrund der stark eingeschränkten Verfügbarkeit und Qualität von Beobachtungsdaten jedoch schwierig. Im Rahmen des im Februar 2021 angelaufenen Projekts „NZ-PROXY“ werden krustenbildende coralline Rotalgen (KCA) als Klimaindikatoren eingesetzt, um – analog zu dendrochronologischen Rekonstruktionen der terrestrischen Lufttemperatur – die Beobachtungszeitreihe der Meeresoberflächentemperatur (SST) in Neuseeland bis 1850 zu verlängern. KCA zeichnen sich im Vergleich zu anderen marinen Klima-Indikatoren u.a. durch ihre weltweite Verbreitung, zeitlich hochaufgelöste Information und relativ leichte Zugänglichkeit aus. Der mithilfe der KCA neu gewonnene, historische SSTDatensatz soll für die Evaluierung von GCMs in der Neuseelandregion verwendet werden und somit die Auswahl geeigneter GCM-Inputdatensätze für regionale Atmosphärenmodelle und die Verbesserung regionaler Klimamodellierung ermöglichen. Aufgrund seiner einzigartigen geographischen Lage ist Neuseeland von ozeanischer und atmosphärischer Klimavariabilität gleichermaßen beeinflusst; Variationen der SST schlagen sich dort auf einer Vielzahl von räumlichen und zeitlichen Skalen nieder und sind bis hin zu Temperaturanomalien und Gletschermassenbilanzänderungen im Hochgebirge der Südlichen Alpen statistisch detektierbar. Eine korrekte Simulation der SST durch GCMs ist daher essentiell und kann im Rahmen der regionalen Modellierung dazu beitragen, die physikalischen Mechanismen zu entschlüsseln, die großräumige SST-Signale in lokale Klimaanomalien umwandeln. Im Vortrag werden der Forschungsansatz sowie erste Ergebnisse aus Laboranalysen und Modellierungen vorgestellt. <br

Data-driven modelling of hydraulic-head time series: results and lessons learned from the 2022 Groundwater Time Series Modelling Challenge - Collenteur, Raoul A.; Haaf, Ezra; Bakker, Mark; Liesch, Tanja; Wunsch, Andreas; Soonthornrangsan, Jenny; White, Jeremy; Martin, Nick; Hugman, Rui; De Sousa, Ed; Vanden Berghe, Didier; Fan, Xinyang; et al. (Hydrology and Earth System Sciences, 2024)
This paper presents the results of the 2022 Groundwater Time Series Modelling Challenge, where 15 teams from different institutes applied various data-driven models to simulate hydraulic-head time series at four monitoring wells. Three of the wells were located in Europe and one was located in the USA in different hydrogeological settings in temperate, continental, or subarctic climates. Participants were provided with approximately 15 years of measured heads at (almost) regular time intervals and daily measurements of weather data starting some 10 years prior to the first head measurements and extending around 5 years after the last head measurement. The participants were asked to simulate the measured heads (the calibration period), to provide a prediction for around 5 years after the last measurement (the validation period for which weather data were provided but not head measurements), and to include an uncertainty estimate. Three different groups of models were identified among the submissions: lumped-parameter models (three teams), machine learning models (four teams), and deep learning models (eight teams). Lumped-parameter models apply relatively simple response functions with few parameters, while the artificial intelligence models used models of varying complexity, generally with more parameters and more input, including input engineered from the provided data (e.g. multi-day averages). The models were evaluated on their performance in simulating the heads in the calibration period and in predicting the heads in the validation period. Different metrics were used to assess performance, including metrics for average relative fit, average absolute fit, fit of extreme (high or low) heads, and the coverage of the uncertainty interval. For all wells, reasonable performance was obtained by at least one team from each of the three groups. However, the performance was not consistent across submissions within each group, which implies that the application of each method to individual sites requires significant effort and experience. In particular, estimates of the uncertainty interval varied widely between teams, although some teams submitted confidence intervals rather than prediction intervals. There was not one team, let alone one method, that performed best for all wells and all performance metrics. Four of the main takeaways from the model comparison are as follows: (1) lumped-parameter models generally performed as well as artificial intelligence models, which means they capture the fundamental behaviour of the system with only a few parameters. (2) Artificial intelligence models were able to simulate extremes beyond the observed conditions, which is contrary to some persistent beliefs about these methods. (3) No overfitting was observed in any of the models, including in the models with many parameters, as performance in the validation period was generally only a bit lower than in the calibration period, which is evidence of appropriate application of the different models. (4) The presented simulations are the combined results of the applied method and the choices made by the modeller(s), which was especially visible in the performance range of the deep learning methods; underperformance does not necessarily reflect deficiencies of any of the models. In conclusion, the challenge was a successful initiative to compare different models and learn from each other. Future challenges are needed to investigate, for example, the performance of models in more variable climatic settings to simulate head series with significant gaps or to estimate the effect of drought periods.
CRIS-Team Scopus Importer:2025-02-04

Data equity in paleobiology: progress, challenges, and future outlook - Dunne, Emma; Chattopadhyay, Devapriya; Dean, Christopher D.; Dillon, Erin M.; Dowding, Elizabeth; Godoy, Pedro L.; Smith, Jansen A.; Raja, Nussaïbah Begum (Paleobiology, 2025)
In the last 50 years, the field of paleobiology has undergone a computational revolution that opened multiple new avenues for recording, storing, and analyzing vital data on the history of life on Earth. With these advances, the amount of data available for research has grown, but so too has our responsibility to ensure that our data tools and infrastructures continue to innovate in order to best serve our diverse community. This review focuses on data equity in paleobiology, an aspirational goal, wherein data in all forms are collected, stored, shared and analyzed in a responsible, equitable, and sustainable manner. While there have been many advancements across the last five decades, inequities persist. Our most significant challenges relate to several interconnected factors, including ethical data collection, sustainable infrastructure, socioeconomic biases, and global inequalities. We highlight the ways in which data equity is critical for paleobiology and stress the need for collaborative efforts across the paleobiological community to urgently address these data equity challenges. We also provide recommendations for actions from individuals, teams, academic publishers, and academic societies in order to continue enhancing data equity and ensuring an equitable and sustainable future for our field.
CRIS-Team Scopus Importer:2025-05-09

Dead end for endemic plant species? A biodiversity hotspot under pressure - Kidane, Yohannes O.; Steinbauer, Manuel; Beierkuhnlein, Carl (Global Ecology and Conservation, 2019)
Tropical high mountains are hosting important hot spots of biodiversity on small mostly remote areas. Recently, these precious ecosystems are under threat from land use change and climate change coupled with other local drivers of biodiversity loss. Along the East African Afroalpine ecosystems, area above the treeline have experienced long-term spatial isolation and extreme climatic conditions (climatic factors such as low mean temperature, diurnal freeze-thaw cycles and other energy-related factors) which lead to the formation of "Sky Island" like ecosystems that are rich in endemics and unique. The Bale Mountains of Ethiopia are home to the largest tropical alpine plateau in Africa, with no spacious high summits that provide space for upward shift of species. Here, we studied plant species diversity and distribution patterns and tested potential future impacts of climate change induced warming on those patterns. This study is based on distribution data acquired from nested circular plots along an elevational gradient ranging from 2000m asl to the highest elevation (4385 m asl). We find hump shaped species richness patterns on both aspects, i.e. the dry north-eastern and the wet monsoon exposed south-western escarpment. In addition, the proportion of endemic species increases monotonically towards the summit on all slopes. Based on our data and literature, we project future climate impact for three regional warming scenarios (+2 degrees C, + 3 degrees C and + 4 degrees C). We quantify the future range of 114 endemic plant species based on their current occurrence records applying a lapse rate of 0.6 degrees C per 100 m of elevation. We find that future climate change would significantly alter species distribution patterns with pronounced impact on the unique ecosystems and endemic species restricted to the afroalpine plateau. Very likely this will be leading to the extinction of many endemic species. Published by Elsevier B.V.
CRIS-Team WoS Importer:2019-08-09

Death of a Sand Sea: An active erg systematically buried by the Etendeka flood basalts of NW Namibia. - Jerram, Dougal A.; Mountney, Nigel; Howell, John; Long, Dan; Stollhofen, Harald (Journal of the Geological Society, 2000)
Here we report on a 'fossilized' sand sea that was progressively engulfed by the basal Etendeka flood basalts in NW Namibia. Preserved relict aeolian landforms include transverse barchanoid dunes and isolated barchan dunes. Present-day preferential erosion of the lava flows exhumes relict aeolian bedforms preserved in the position in which they were migrating at the time of burial (c. 133 Ma). A passive eruption style of inflated pahoehoe flows has preserved the bedforms without significant deformation. The sediment interlayers record a decrease in sand supply and a change in palaeowind direction, which may have been driven by the ongoing break-up of west Gondwana, or may be a direct result of the widespread volcanism itself.
UnivIS-Import:2015-03-09:Pub.2000.nat.dgeo.IGM.LG.deatho
Keywords: Aeolian features; Etendeka; Flood basalts; Namibia

Deciphering kinetic, metabolic and environmental controls on stable isotope fractionations between seawater and the shell of Terebratalia transversa (Brachiopoda). - Joachimski, Michael; et al. (Chemical Geology, 2003)
This study presents carbon and oxygen stable isotope data obtained from high-resolution sampling (<500 μm) of the brachiopod Terebratalia transversa from the San Juan Islands (Washington State, USA). The aim of this study is to unravel the respective effects of physiological and environmental controls on the stable isotopic composition of brachiopod shell calcite. Based on an SEM study of the shell, a three-dimensional sampling was performed in order to investigate carbon and oxygen isotope variations along isochrons and ontogenetic transects. The primary as well as the outer part of the secondary shell layer display large and variable isotopic offsets as high as -7‰ for δ 13C and -6‰ for δ 18O relative to expected equilibrium values. The significant positive correlations between δ 18O and δ 13C values indicate that the isotopic compositions of these shell domains are mainly controlled by kinetic isotope fractionation effects. The ontogenetic δ 13C and δ 18O variations can be used to establish a growth curve of the studied specimen whose age is estimated close to 8 years. The extent of apparent O-18 disequilibrium observed in this study is about as large as any yet measured in any organism, which makes this brachiopod an interesting and important case. The carbon and oxygen isotope compositions increase from the outer towards the inner part of the secondary layer, where they reach values of 0-0.8‰ and -0.8‰ to -0.2‰, respectively. Corresponding calculated temperatures are between 12 and 13.8 °C and fall in the range of seawater temperatures recorded off the San Juan Islands (7-13 °C). These results suggest that the calcite fibres were secreted more and more slowly during the thickening of the shell throughout the animal's life, finally approximating isotopic equilibrium.This study illustrates that the stable isotopic composition of the modern brachiopod T. transversa is predominantly influenced by kinetic fractionation and, to a minor degree, by metabolic effects. Except for the innermost part of the shell, the measured isotope ratios do not reflect environmental conditions during shell precipitation. It remains to be tested by comparable studies whether other modern brachiopod species or even fossil brachiopods reflect comparable fractionation effects. These results point out the need for re-examination of Paleozoic oceanographic conditions. © 2003 Elsevier B.V. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2003.nat.dgeo.IGM.LG.deciph
Keywords: Carbon-13; Kinetic effects; Oxygen-18; Paleozoic; Respiration

Deciphering protoliths of the (U)HP rocks in the Makbal metamorphic complex, Kyrgyzstan: geochemistry and SHRIMP zircon geochronology - Konopelko, Dmitry; Klemd, Reiner (European Journal of Mineralogy, 2016)
The (ultra)high-pressure (U) HP Makbal metamorphic complex (MMC) belongs to a chain of early Paleozoic (U) HP terranes to the south of the Paleo-Kazakhstan continent, a major component of the Central Asian Orogenic Belt. We present geochemical characteristics, reconstructions of geodynamic settings and constraints on the emplacement and depositional ages of metamorphosed intrusive and sedimentary rocks of the MMC. The MMC comprises variably metamorphosed juxtaposed packages of mica schists, hosting boudins of metamorphosed mafic rocks, metaquartzites and metacarbonates in a tectonic mélange. The rocks, metamorphosed under (U) HP conditions, are situated in the central part of the terrane. The UHP garnet–talc – chloritoid schists are believed to have formed from immature pelitic sediments with maximum depositional ages of 700 – 650 Ma. The (U) HP metaquartzites comprise mature sediments derived from a Paleoproterozoic continental source. They were formed in a passive-margin environment and have a maximum depositional age of ca. 1600 Ma. The chemical composition of the MMC metabasic rocks is compatible with subalkaline tholeiitic basalts with E-MORB compositions; however, some samples have N-MORB and OIB affinities. The ages of zircon xenocrysts from the metabasic rocks show that the mafic intrusions are probably younger than ca. 700 Ma. The metabasic rocks represent dikes and sills emplaced into immature pelitic sediments in a rift-related or continental-slope environment at the final stages of the Rodinia break up (700–600 Ma) when shallow mantle melting produced relatively primitive tholeiitic compositions. The whole sequence, including the quartzites, was later juxtaposed with other passive-margin sediments and metamorphosed under (U) HP conditions in a Caledonian subduction zone between 500 and 475 Ma. The ages of detrital zircon grains from the MMC rocks indicate derivation from a Paleoproterozoic continental source and match the age pattern characteristic for the Northern Tien Shan, with major peaks at 1.95–1.75 Ga and smaller peaks between 2.7 and 2.5 Ga and at ca. 1.0 Ga. The ages between 1.65 and 1.4 Ga are uncharacteristic for the Kyrgyz Northern Tien Shan, instead may be correlated with recently documented voluminous early Mesoproterozoic arc magmatism in the Central Tien Shan Arc Terrane in China. The resetting of the U– Th–Pb system and the growth of new zircon in the MMC rocks were probably defined by the permeability to aqueous fluids. An age of 456 ± 4 Ma, obtained for the rims of zircon xenocrysts from a small amphibolite boudin in the southern part of the MMC, corresponds with the age of an adjacent Ordovician granite and indicates that Paleozoic intrusions could have provided sufficient heat to cause resetting and/or growth of new zircon in the MMC rocks.<br
Keywords: tien shan (tianshan); geodynamic; eclogite; provenance; makbal (u)hp complex; geochemistry; u–pb zircon age; shrimp; setting

Decoding sea surface and paleoclimate conditions in the eastern Mediterranean over the Tortonian-Messinian Transition - Kontakiotis, G.; Besiou, E.; Antonarakou, A.; Zarkogiannis, S. D.; Kostis, A.; Mortyn, P. G.; Moissette, P.; Cornée, J. J.; Schulbert, Christian; Drinia, H.; Anastasakis, G.; Karakitsios, V. (Palaeogeography, Palaeoclimatology, Palaeoecology, 2019)
New sedimentological, micropaleontological and geochemical data from the Upper Miocene pre-evaporitic sedimentary sequence of the Faneromeni section (Crete Island, eastern Mediterranean) revealed a stepwise restriction of the Mediterranean Sea preceding the Messinian Salinity Crisis (MSC), which was modulated by a sedimentary cyclicity responding to orbital parameters. This cyclicity is manifested by lithological alternations from laminated to indurated homogeneous marls and clayey limestones, and covers the Tortonian-Messinian Transition (TMT; 7.6–6.7 Ma). This time window covers the successive closure of the marine Mediterranean-Atlantic gateways, which culminated in the onset of the MSC. In the present study, we present the first evidence for changes in the upper water column reflected by sea surface temperature (SST) and salinity (SSS) variations that correlate with pronounced paleoclimatic fluctuations. Planktonic foraminiferal isotopes, in combination with paired mixed layer Sr/Ca-derived SST data, reveal that the very warm late Tortonian interval has been followed by a strong long-term cooling ( 10 °C) and desalination ( 10‰) trend during the earliest Messinian, attributed to the paroxysmal phase of the so-called “siphon” event. In particular, the climate shift that occurred at the end of a global carbon isotope (δ13C) decrease suggests that changes in the carbon cycle were instrumental in driving late Miocene climate dynamics (cooling and aridity) in the progressively isolated eastern Mediterranean Sea. The observed salinity variability during this time interval also provides further insights about seasonal freshwater inputs and gives new support to the much-debated hydrologic regime (linear salinity increase vs step-function evolution with strong salinity fluctuations) preceding the deposition of evaporites. The novel methodology of foraminiferal Sr/Ca paleothermometry and results of this study could have numerous potential applications to other regions and relevant extreme geological events. Therefore, in the near future we expect this approach to add important new information to our understanding of Neogene climates.
CRIS-Team Scopus Importer:2019-08-16
Keywords: Hydrological cycle; Late Miocene; Messinian Salinity Crisis (MSC); Sea surface salinity (SSS); Siphon cooling event; Sr/Ca paleothermometry

Deepening our understanding of bioactive glass crystallization using TEM and 3D nano-CT - Contreras Jaimes, Altair T.; de Pablos-Martín, Araceli; Hurle, Katrin; Martins de Souza e Silva, Juliana; Berthold, Lutz; Kittel, Thomas; Boccaccini, Aldo R.; Brauer, Delia S. (Journal of the European Ceramic Society, 2021)
One key issue influencing a broader application of Bioglass 45S5 in tissue engineering is its inherent crystallization tendency, severely limiting the mechanical strength of 3D porous scaffolds. Despite numerous studies, Bioglass 45S5 crystallization is not yet fully understood with regard to the mechanisms involved or morphology of the crystal phases forming. Here we show how two cutting-edge imaging techniques, state-of-the-art transmission electron microscopy (TEM) with image correction including energy dispersive X-ray spectroscopy and X-ray nano-computed tomography (nano-CT), allowed us to visualize changes in microstructure from near-nucleation to almost full crystallization in bulk Bioglass 45S5. At early times of heat treatment at 660 °C the formation of phase-separated nano-droplets within the glassy matrix was observed. Later, besides surface crystallization, bulk crystallization of combeite spheres was predominant. The formation of the first combeite spheres, their coarsening with time and finally their merging at near full crystallization were recorded by in situ high-temperature optical microscopy videos. The 3D nature of these spheres was confirmed by nano-CT, while TEM showed that their internal structure was composed of sub-micron grains. X-ray diffraction analysis at early time points showed a much higher crystalline fraction in bulk samples compared to powder samples, highlighting the influence of processing and sample morphology. These results show the importance of using complementary techniques for gaining insight into the crystallization process in the volume. In addition, we show that TEM and nano-CT are suitable characterization techniques to visualize the crystallization even in fast crystallizing systems, such as bioactive glasses.
CRIS-Team Scopus Importer:2021-04-19
Keywords: Biomaterials; Crystallization; Non-metallic glasses; Transmission electron microscopy; X-ray computed tomography

Deeper insights: The potential of X-ray micro-computed tomography (μCT) in microplastic studies - Löder, Martin; Wittmann, Marie; Teichert, Sebastian; Schulbert, Christian; Oster, Jakob; Laforsch, Christian (MICRO 2020 - Fate and Impacts of Microplastics: Knowledge and Responsibilities, 2020)
Since the topic of microplastics and the detection of these small plastic particles is becoming increasingly important in science, it is necessary to establish methods that allow for a non-destructive detection of microplastics in research objects. Especially with respect to the detection of environmentally relevant concentrations of microplastics in experimental organisms without destroying their body structures X-ray micro-computed tomography (μCT) is a very promising technique. We report first results of experiments with radiopaque polyurethane microplastics. Ten terrestrial and aquatic invertebrate species were selected as experimental organisms to provide a cross-section of different invertebrate taxa. In nine of the ten organisms used, microplastic particles could be easily detected by μCT, and in most cases the exact position of the plastic in the digestive tract of the individual organisms could also be determined. In animals with a solid cuticle, the method is also well suited for detecting external structures. In order to be able to make more precise statements about the position of the microplastics in the body structure of the animals radio-opaque staining methods are available and have to be tested in future studies. The method described here is particularly suitable for non-destructive detection of microplastics in organisms at low natural microplastic concentrations in experiments on the uptake and trophic transfer of microplastics.<br

Deep solid-state equilibration and deep melting of plagioclase-free spinel peridotite from the slow-spreading Mid-Atlantic Ridge, ODP Leg 153 - Will, Thomas M.; Schmädicke, Esther; Frimmel, Hartwig E. (Mineralogy and Petrology, 2010)

Deep-time climate legacies affect origination rates of marine genera - Mathes, Gregor; Kießling, Wolfgang; Steinbauer, Manuel J. (Proceedings of the National Academy of Sciences of the United States of America, 2021)
Biodiversity dynamics are shaped by a complex interplay between current conditions and historic legacy. The interaction of short- and long-term climate change may mask the true relationship of evolutionary responses to climate change if not specifically accounted for. These paleoclimate interactions have been demonstrated for extinction risk and biodiversity change, but their importance for origination dynamics remains untested. Here, we show that origination probability in marine fossil genera is strongly affected by paleoclimate interactions. Overall, origination probability increases by 27.8% [95% CI (27.4%, 28.3%)] when a short-term cooling adds to a long-term cooling trend. This large effect is consistent through time and all studied groups. The mechanisms of the detected effect might be manifold but are likely connected to increased allopatric speciation with eustatic sea level drop caused by sustained global cooling. We tested this potential mechanism through which paleoclimate interactions can act on origination rates by additionally examining a proxy for habitat fragmentation. This proxy, continental fragmentation, has a similar effect on origination rates as paleoclimate interactions, supporting the importance of allopatric speciation through habitat fragmentation in the deep-time fossil record. The identified complex nature of paleoclimate interactions might explain contradictory conclusions on the relationship between temperature and origination in the previous literature. Our results highlight the need to account for complex interactions in evolutionary studies both between and among biotic and abiotic factors.
CRIS-Team Scopus Importer:2021-09-10
Keywords: Climate change; Evolution; Fossil record; Macroevolution; Paleoclimate

Deep time climatic and environmental extremes and ecosystem response: an introduction. - Chen, Zhong-Qiang; Joachimski, Michael; Montanez, Isabel; Isbell, John (Gondwana Research, 2014)
UnivIS-Import:2015-03-09:Pub.2014.nat.dgeo.IGM.LG.deepti

Deformation and fluid flow in the Huab Basin and Etendeka Plateau, NW Namibia - Salomon, Eric; Koehn, Daniel; Passchier, Cees; Chung, Peter; Haeger, Tobias; Salvona, Aron; Davis, Jennifer (Journal of Structural Geology, 2016)
The Lower Cretaceous Twyfelfontein sandstone formation in the Huab Basin in NW Namibia shows the effects of volcanic activity on a potential reservoir rock. The formation was covered by the Parana-Etendeka Large Igneous Province shortly before or during the onset of South-Atlantic rifting. Deformation bands found in the sandstone trend mostly parallel to the continental passive margin and must have formed during the extrusion of the overlying volcanic rocks, indicating that their formation is related to South-Atlantic rifting. 2D-image porosity analysis of deformation bands reveals significant porosity reduction from host rock to band of up to 70%. Cementation of the sandstone, linked to advective hydrothermal flow during volcanic activity, contributes an equal amount to porosity reduction from host rock to band when compared to initial grain crushing. Veins within the basaltic cover provide evidence for hot fluid percolation, indicated by spallation of wall rock and colloform quartz growth, and for a later low-temperature fluid circulation at low pressures indicated by stilbite growth sealing cavities. Sandstone samples and veins in the overlying volcanic rocks show that diagenesis of the Twyfelfontein sandstone is linked to Atlantic rifting and was affected by both hydrothermal and low-thermal fluid circulation. (C) 2016 Elsevier Ltd. All rights reserved.
Keywords: Deformation bands; Cataclastic bands; syn-volcanic faulting; Quartz veins; Porosity analysis; South Atlantic rifting

Deformation and granite intrusion in the Sirohi area, SW Rajasthan-Constraints on Cryogenian to Pan-African crustal dynamics of NW India - de Wall, Helga; Pandit, Manoj K.; Sharma, Kamal K.; Schöbel, Stefan; Just, Jana (Precambrian Research, 2014)
Keywords: Balda granite; Cryogenian; NW India; Rodinia; Sirohi region

Deformation and ultrafine dynamic recrystallization of quartz in pseudotachylyte-bearing brittle faults: A matter of a few seconds - Bestmann, Michel; Pennacchioni, Giorgio; Nielsen, Stefan; Göken, Mathias; de Wall, Helga (Journal of Structural Geology, 2012)
Tectonic pseudotachylytes, i.e. quenched friction-induced silicate melts, record coseismic slip along faults and are mainly reported from the brittle crust in association with cataclasites. In this study, we document the occurrence of recrystallization of quartz to ultrafine-grained (grain size 1-2 mu m) aggregates along microshear zones (50-150 mu m thick) in the host rock adjacent to pseudotachylytes from two different faults within quartzite (Schneeberg Normal Fault Zone, Eastern Alps), and tonalite (Adamello fault, Southern Alps) in the brittle crust. The transition from the host quartz to microshear zone interior includes: (i) formation of high dislocation densities; (ii) fine (0.3-0.5 mu m) polygonization to subgrains defined by disordered to well-ordered dislocation walls; (iii) development of a mosaic aggregate of dislocation-free new grains. The crystallographic preferred orientation (CPO) of quartz towards the microshear zone shows a progressive misorientation from the host grain, by subgrain rotation recrystallization, to a nearly random CPO possibly related to grain boundary sliding. These ultrafine aggregates appear to be typically associated with pseudotachylytes in nature. We refer the crystal plastic deformation of quartz accompanied by dramatic grain size refinement to the coseismic stages of fault slip due to high differential stress and temperature transients induced by frictional heating. Microshear zones localized on precursory fractures developed during the stages of earthquake rupture propagation and the very initial stages of fault slip. Thermal models indicate that the process of recrystallization, including recovery processes, occurred in a time lapse of a few tens of seconds. (C) 2011 Elsevier Ltd. All rights reserved.
WW1::919
Keywords: Earthquakes; Pseudotachylyte; Crystal plastic deformation; Quartz; Microstructure; TEM; EBSD

Deformation-induced Japan twinning in quartz during incipient mylonitization - Bestmann, Michel; Pennacchioni, Giorgio; Grasemann, Bernhard (Geology, 2021)
Many crystalline rocks of the continental crust contain coarse-grained quartz as a main mineral (e.g., granitoids). Incipient deformation of coarse quartz, which likely controls the accumulation of bulk strain in heterogeneously deformed crustal rock volumes, commonly develops microshear zones (MSZs) of localized recrystallization. At mid-crustal conditions, where quartz deformation is mostly accomplished by subgrain rotation recrystallization, grains of MSZs can show an abrupt change in crystallographic orientation (large misorientation angle) with respect to the host quartz that is still not fully understood. We analyzed MSZs (20–200 μm thick) from deformed coarse-grained (millimeter grain size) quartz veins in the Austroalpine Schobergruppe (Eastern Alps). Electron backscatter diffraction analysis reveals that the MSZs are characterized by a nearly 90° misorientation angle between the c-axes of the host and new grains, which also share one m and one 1122 pole, compatible with Japan twinning. This abrupt switch of the c-axis orientation can promote geometrical softening and shear localization. So far, Japan twinning has been interpreted as a growth feature. We show that deformation-induced twinning in quartz, including Japan and Dauphiné twinning, can play an important role in initiation of crystal-plastic deformation within the crust.
CRIS-Team Scopus Importer:2021-11-19

Deformation in the Aravalli Supergroup, Aravalli-Delhi Mobile Belt, NW India and Tectonic Significance - Hahn, Gregor; Kodl, Georg; de Wall, Helga; Schulz, Bernhard; Bestmann, Michel; Chauhan, Narendra Kumar (Structural Geometry of Mobile Belts of the Indian Subcontinent, 2020)
Sediments of the Aravalli Supergroup have acquired a complex superposed fold pattern during Neoproterozoic amalgamation (Grenvillian Orogeny) of north Indian blocks (Marwar block, Bundelkhand craton, North Delhi crustal block) and collision with the Central Indian Craton. The Upper Aravalli metasediments reveal a prograde mono-metamorphic history with continuous increase in metamorphic conditions towards the Delhi Supergroup contact. The transition from phyllites to garnet-bearing mica schist is accompanied by strain increase seen in tightening of F2 folds. Microstructures and deformationmechanism in quartz document an increasing temperature gradient from similar to 280 to 500 degrees C towards the Aravalli-Delhi contact. Garnets, grown prior to the contact-parallel, pervasive second cleavage indicate crystallisation along a prograde P-T-path from 400 degrees C/4 kbar to 500 degrees C/7 kbar. Older metamorphic records in the northern Aravalli-Delhi mobile belt sector (e.g. Sandmata Complex, Mangalwar Complex, and North Delhi Terrane) cannot be related with deformation and metamorphism in the Aravalli Supergroup. Considering the pattern of bivergent thrusts with the Neoproterozoic active continental margin along the western side of the Delhi Fold Belt, the lack of any magmatic signature and the inferred contractional fold and thrust deformation along the eastern proximity can be interpreted as a retro-wedge setting.
CRIS-Team WoS Importer:2021-10-08
Keywords: Aravalli-Delhi contact; Aravalli supergroup; Multiple phases of folding; Quartz microstructure; Garnet thermobarometry; NW India

Deformation mechanism and dynamic response of Huangtupo landslides in Three Gorges Reservoir in case of frequent microseisms - Jiang, Jiwei; Pan, Jiajun; Zhang, Wei; Xiang, Wei; Rohn, Joachim (8th European Conference on Numerical Methods in Geotechnical Engineering, NUMGE 2014, 2014)

Deglacial–Holocene Svalbard paleoceanography and evidence of meltwater pulse 1B - Tian, Skye Yunshu; Yasuhara, Moriaki; Hong, Yuanyuan; Huang, Huai-Hsuan; Iwatani, Hokuto; Chiu, Wing Tung Ruby; Mamo, Briony; Okahashi, Hisayo; Rasmussen, Tine L. (Quaternary Science Reviews, 2020)
Better understanding of deglacial meltwater pulses (MWPs) is imperative for future predictions of human-induced warming and abrupt sea-level change because of their potential for catastrophic damage. However, our knowledge of the second largest meltwater pulse MWP-1B that occurred shortly after the start of the Holocene interglacial remains very limited. Here, we studied fossil ostracods as paleoenvironmental indicators of water depth, salinity, and temperature in two marine sediment cores from Storfjorden, Svalbard margin (the Arctic Ocean), to investigate near-field (i.e. areas located beneath continental ice sheets at the Last Glacial Maximum) evidence of MWP-1B. The depositional environment changed from a cold bathyal environment to a warmer bathyal environment at ∼11,300 yr BP indicating incursion of warm Atlantic water into the Nordic seas, and eventually to a cold neritic environment by ∼11,000 yr BP because of melting of the Svalbard-Barents Sea ice sheet and resultant isostatic rebound. This process corresponds to rapid relative sea-level fall of 40–80 m of MWP-1B from ∼11,300 to 11,000 yr BP.
CRIS-Team Scopus Importer:2020-03-17
Keywords: Arctic ocean; Holocene; Micropaleontology; Neoglaciation; Ostracoda; Paleoceanography; Sea level change; The last deglaciation

Degradable bone substituition material based on cellular Ca-phosphates - Götz-Neunhoeffer, Friedlinde; Göbbels, Matthias; Enderle, Ralph; Neubauer, Jürgen; Zeschky, Jürgen (Applied Mineralogy, 2004)
UnivIS-Import:2015-04-16:Pub.2004.nat.dgeo.IGM.LM.degrad

Demise of the last two spire-bearing brachiopod orders (Spiriferinida and Athyridida) at the Toarcian (Early Jurassic) extinction event - Vörös, Attila; Kocsis, Ádám; Palfy, Jozsef (Palaeogeography, Palaeoclimatology, Palaeoecology, 2016)
Brachiopods were severely hit by several mass extinctions which fundamentally shaped their long evolutionary history. After the devastating end-Permian extinction, the fate of the four surviving orders differed significantly during the Triassic and Jurassic. Two orders, the rhynchonellids and terebratulids are extant today, whereas spiriferinids and athyridids, which possess spiral brachidia, suffered heavy losses at the end of the Triassic and became extinct in the Early Jurassic Toarcian event. Although the doom of the spire-bearing orders has been thought to be related to physiological traits, extinction selectivity across the end-Triassic and Toarcian event has not been rigorously assessed previously, and the reasons for their demise at the later and lesser Toarcian event, rather than at the earlier and greater end-Triassic crisis remained unexplored. Using primarily the Paleobiology Database, we constructed diversity curves, estimated taxonomic rates, and assessed the temporal changes in geographic distribution of the two spire-bearing and two other orders in the Triassic-Jurassic interval. After shared trends and similar origination rates in the post-Permian recovery leading to a Late Triassic diversity maximum, the end-Triassic extinction was selective and preferentially eliminated the spire-bearers. In contrast to the rebound of rhynchonellids and terebratulids, spire-bearers failed to recover in the Early Jurassic, and their repeated selective extinction at the Toarcian event led to their final demise. The end-Triassic event also terminated the worldwide geographic distribution of spire-bearers, confining them to the Western Tethys, whereas the other groups were able to re-establish their cosmopolitan distribution. The morphologically diverse spire-bearers represent specialized adaptation, which further increased their extinction vulnerability compared to the other groups with conservative biconvex shell morphology. Another key difference is the physiological disadvantage of the fixed lophophore and passive feeding of spire-bearers, which became critical at times of increased environmental stress. The spire-bearing spiriferinids and athyridids were “dead clades walking” in the Early Jurassic and their disappearance in the Early Toarcian represents the last major, order-level extinction event for the brachiopods.
Keywords: Diversity; Paleobiology Database; End-Triassic; Mass extinction; Paleobiogeographic distribution

Density Effects on Mixing in Porous Media: Multi-dimensional Flow-Through Experiments and Model-Based Interpretation - Ye, Yu; Liu, Sen; Chiogna, Gabriele; Lu, Chunhui; Rolle, Massimo (Transport in Porous Media, 2025)
Density effects can strongly impact flow, solute transport and mixing processes in porous media. In this study, we systematically investigate and compare variable-density flow and transport in quasi two-dimensional and fully three-dimensional porous media using laboratory flow-through experiments and numerical simulations. Sodium chloride was used as conservative tracer in the experiments, with injected concentrations of 4.8 and 20 g/l, respectively. Average flow velocities of 1, 3, 9 and 27 m/d were selected to represent a wide range of advection-dominated flow conditions (Péclet number 3–100). Numerical simulations were performed to quantitatively interpret the bench-scale experiments, as well as to extend the investigation to a larger domain, allowing the analysis of the impact of a wider range of injected concentrations (0.01–65 g/l) and average flow velocities (0.5–30 m/d). Our results reveal distinct plume patterns, including fingering instabilities, sinking and secondary motion, depending on the density difference, on the average flow velocity and on the dimensionality of the system. The latter plays a key role in causing convective rolls, in the rapid sinking of the injected electrolyte plume, and in preventing the onset of fingering instabilities in the 3-D setups. The outcomes of the flow-through experiments, numerical simulations, and Shannon entropy analysis of mixing enhancement by density gradients illuminate a different mixing behavior, under distinct advection-dominated flow regimes, in quasi 2-D and fully 3-D flow-through systems.
CRIS-Team Scopus Importer:2025-04-01
Keywords: Density effects; Flow-through experiments; Mixing; Porous media; Solute transport

Depositional conditions and revised age of the Permo-Triassic microbialites at Gaohua section, Cili County (Hunan Province, South China) - Wang, Lina; Wignall, Paul B.; Wang, Yongbiao; Jiang, Haishui; Sun, Yadong; Li, Guoshan; Yuan, Jinling; Lai, Xulong (Palaeogeography, Palaeoclimatology, Palaeoecology, 2016)
Keywords: Conodont; Dysoxic; Microbialite; Permian-Triassic

Depositional controls on sediment properties in dryland rivers: Influence on near-surface diagenesis - Henares, Saturnina; Donselaar, Eric Marinus; Caracciolo, Luca (Earth-Science Reviews, 2020)
Sandy braided dryland rivers, deposited under arid to semi-arid conditions, constitute important clastic reservoirs worldwide whose reservoir quality reflects the effect of primary sediment properties on near-surface diagenetic processes. A literature review is presented of existing facies models, based on geomorphological analysis of modern perennial braided rivers, further illustrated with own outcrop and subsurface examples of dryland river deposits in: (a) Argana Basin (Triassic, Morocco), (b) Iberian Meseta (Triassic, Central SE Spain), (c) Huesca Fluvial Fan (Miocene, Spain) and (d) Rotliegend hydrocarbon reservoir in the Southern Permian Basin (The Netherlands). The facies models, combined with the analyses of the rock record, provides a comprehensive depositional framework where the influence of depositional characteristics, such as grain-size and sorting variations, interstitial clay distribution and composition and amount of intrabasinal components, on the extent and pathway of near-surface mechanical and chemical processes can be investigated. The particular dryland setting is characterized by prolonged periods of inactivity and short, episodic periods of peak discharge, which lead to the transport and deposition of poorly-sorted, clay-rich extra- and intraformational conglomeratic sediments upstream. Downstream, channels, mid-channel and bank-attached bars develop with conspicuous anisotropic trough and tabular cross-stratified sandstones. The most common near-surface diagenetic processes that alter the textural properties of these deposits are the rapid decrease of porosity and permeability due to grain-rearrangements and mechanical compaction of mud intraclasts along with pervasive early carbonate cementation. The results of this study will help to better configure the boundary conditions (e.g., external versus local supply for carbonates cements) in state-of-the-art reservoir quality forward models for ancient dryland river sandstones, which are especially prominent in Devonian, Permian, Triassic and Jurassic reservoir setting

Deposition, persistence and turnover of pollutants: First results from the EU project AquaTerra for selected river basins and aquifers - Barth, Johannes; et al. (Science of the Total Environment, 2007)

Depth-related controls on the quantitative composition of rhodolith matrices in the high Arctic - Pyko, Ines Anna; Wisshak, Max; Teichert, Sebastian (Aquatic Conservation-Marine and Freshwater Ecosystems, 2025)
The calcareous matrix of rhodoliths can be composed of one or more crustose coralline algae (CCA) taxa as well as a mixed assemblage of various encrusting organisms. Studies on modern and fossil rhodoliths assume such associations to vary with water depth. Our study explores the quantitative biological composition of calcareous rhodolith matrices along a bathymetric gradient at the Arctic Svalbard archipelago. Using a methodological combination of virtual micro-CT cross-sections with a modified point counting approach, we found five different taxonomic groups: CCA, bivalves, serpulids, bryozoans and balanids. While water depth does not influence the general taxon richness as well as the abundance of bivalves, it significantly affects the proportional matrix composition of encrusting organisms by a combination of environmental factors and biological interactions. The decrease in CCA skeletal material with increasing water depth is significantly governed by impaired irradiance conditions. Regular rhodolith movement in shallow waters fosters the proportion of CCA, while decreased movement in deeper waters spurs the proportion of other encrusters. This potentially results from post-mortem fouling of dead rhodolith parts followed by a recolonization with slow-growing CCA species Boreolithothamnion glaciale. Our results highlight mechanisms controlling the biogenic composition of calcareous rhodolith matrices and underline the potential of matrices compositions for palaeogeography and palaeobathymetry. Our study contributes to an improved understanding of the composition and developmental patterns of rhodoliths. This can add to a better comprehension of the respective ecosystems on a broader scale and be beneficial for conservation purpose
Keywords: Arctic; crustose coralline algae; point counting; polar carbonates; rhodoliths; taxonomic composition; X-ray micro- computed tomography

Depth-related controls on the quantitative taxonomic composition of rhodoliths - Pyko, Ines Anna; Wisshak, Max; Teichert, Sebastian (13th International Symposium on Fossil Algae, 2024)
The calcareous matrix of rhodoliths can be composed of one or more crustose coralline algal (CCA) taxa as well as a mixed assemblage of various encrusting organisms. Morphology analyses of the inner arrangement and assemblages of organisms forming rhodoliths can provide valuable information to reconstruct palaeoenvironmental and palaeoclimatic condition (Basso et al. 1998, Aguirre et al. 2017) Descriptive studies on modern and fossil rhodoliths assume associations with water depth. Here we explore the quantitative biological composition of calcareous rhodolith matrices along a bathymetric gradient at the Arctic Svalbard archipelago. We hypothesize that (1) the composition of calcareous rhodolith matrices is taxonomically quantifiable and that (2) this quantitative composition is controlled by water depth, implying that (3) the matrix composition could be used for (palaeo-)bathymetrical reconstructions. Using a methodological combination of virtual micro-CT cross-sections with a modified point counting approach, we distinguished five different taxonomic groups: CCA, bivalves, serpulids, bryozoans, and balanids. The identified matrix component CCA is mainly represented by the species Boreolithothamnion glaciale Kjellman) Gabrielson et al. (2023) (Basionym Lithothamnion glaciale Kjellman, 1883), which is the dominant CCA species in Mosselbukta. The identified matrix component bivalves are represented by the drilling bivalve species Hiatella arctica (Linnaeus, 1767). The other taxa, serpulids (family Serpulidae), balanids (family Balanidae), and bryozoans (phylum Bryozoa) could not be identified to species level. While water depth does not influence the general taxon richness as well as the abundance of bivalves, it significantly affects the proportional matrix composition of encrusting organisms by a combination of environmental factors and biological interactions. The decrease in CCA skeletal material with increasing water depth is significantly governed by impaired irradiance conditions. Regular rhodolith movement in shallow waters fosters the proportion of CCA, while decreased movement in deeper waters spurs the proportion of heterotrophic encrusters. This results from post-mortem fouling of dead rhodolith parts followed by a recolonization with slow-growing CCA. Our results highlight new mechanisms controlling the biogenic composition of calcareous rhodolith matrices and the potential of quantitative matrix compositions for palaeogeography and -bathymetry. However, it also stresses the importance of sufficiently large sample sizes, ideally deriving from different facies types. The introduced methodological combination allows for a straightforward and non-destructive identification and quantification of rhodolith matrix components and also provides a new tool for rhodolith-focused quantitative research from a more general perspectiv

Depths of partial crystallization and H2O contents of MORB inferred from glass compositions: phase equilibria simulations of basalts at the MAR near Ascension Island (7°-11°S). - Almeev, Renat; Holtz, Francois; Koepke, Jürgen; Haase, Karsten; Devey, Colin (Journal of Petrology, 2008)
Phase equilibria simulations were performed on naturally quenched basaltic glasses to determine crystallization conditions prior to eruption of magmas at the Mid-Atlantic Ridge (MAR) east of Ascension Island (7–11°S). The results indicate that mid-ocean ridge basalt (MORB) magmas beneath different segments of the MAR have crystallized over a wide range of pressures (100–900 MPa). However, each segment seems to have a specific crystallization history. Nearly isobaric crystallization conditions (100–300 MPa) were obtained for the geochemically enriched MORB magmas of the central segments, whereas normal (N)-MORB magmas of the bounding segments are characterized by polybaric crystallization conditions (200–900 MPa). In addition, our results demonstrate close to anhydrous crystallization conditions of N-MORBs, whereas geochemically enriched MORBs were successfully modeled in the presence of 0·4–1 wt% H<sub style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-width: 0px; border-right-width: 0px; border-bottom-width: 0px; border-left-width: 0px; border-style: initial; border-color: initial; outline-style: none; font-weight: inherit; font-style: inherit; font-size: 0.85em; font-family: inherit; line-height: 0; text-align: inherit; vertical-align: sub; ">2O in the parental melts. These estimates are in agreement with direct (Fourier transform IR) measurements of H<sub style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-width: 0px; border-right-width: 0px; border-bottom-width: 0px; border-left-width: 0px; border-style: initial; border-color: initial; outline-style: none; font-weight: inherit; font-style: inherit; font-size: 0.85em; font-family: inherit; line-height: 0; text-align: inherit; vertical-align: sub; ">2O abundances in basaltic glasses and melt inclusions for selected samples. Water contents determined in the parental melts are in the range 0·04–0·09 and 0·30–0·55 wt% H<sub style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-width: 0px; border-right-width: 0px; border-bottom-width: 0px; border-left-width: 0px; border-style: initial; border-color: initial; outline-style: none; font-weight: inherit; font-style: inherit; font-size: 0.85em; font-family: inherit; line-height: 0; text-align: inherit; vertical-align: sub; ">2O for depleted and enriched MORBs, respectively. Our results are in general agreement (within ±200 MPa) with previous approaches used to evaluate pressure estimates in MORB. However, the determination of pre-eruptive conditions of MORBs, including temperature and water content in addition to pressure, requires the improvement of magma crystallization models to simulate liquid lines of descent in the presence of small amounts of water.
UnivIS-Import:2015-03-09:Pub.2008.nat.dgeo.IGM.legeo.depths

Der Einfluss Ca-reicher Verbindungen auf das Hydratationsverhalten von Monocalciumaluminat (CA) - Götz-Neunhoeffer, Friedlinde (Tagungsbericht: Ibausil, 15. Internationale Baustofftagung, Band 1, 2003)
UnivIS-Import:2015-03-09:Pub.2003.nat.dgeo.IGM.LM.derein

Deriving early hydration cement paste phase assemblage, microstructure development and elastic properties using thermodynamic simulation and multi-scale material modeling - Jägle, Eva; Timothy, Jithender J.; Jansen, Daniel; Machner, Alisa (Cement and Concrete Research, 2025)
Many hydration models focus on predicting the long-term hydration process and resulting material changes without specifically addressing early hydration within the first day. Here, we present a new approach for predicting early hydration cement paste phase assemblage, microstructure development and elastic properties by applying thermodynamic modeling and simulation as input to a multi-scale material model. Cement dissolution for implementation within the thermodynamic simulation is derived by fitting the five-parameter logistic function (5PL) to experimental data from quantitative X-ray diffraction. Results are compared with simulations using the modified Parrot & Killoh model for cement dissolution. Further, the influence of variations in the calcium sulphate and calcite content of the initial cement phase assemblage is investigated accounting for errors in experimental determination. The proposed model for hydrating cement paste accounts for all phases predicted by the thermodynamic simulation output, two types of C-S-H, as well as concentric growth of hydrates from the surface of the clinker grains. The stiffness of the hydrating cement paste is derived by upscaling the microscopic properties using a multi-level continuum micromechanics homogenization scheme. Model predictions are compared with experimental results from penetration tests and ultrasonic Young's modulus determination. It is shown, that 5PL dissolution modeling in combination with thermodynamic simulation is able to describe early hydration cement phase alterations. The 5PL approach thereby captures initial ettringite formation and accurately describes portlandite precipitation. However, the results are highly dependent on the quality of the experimental data. The results further illustrate, how cement paste stiffness development can be derived by application of low-cost computational methods. The proposed approach enables investigations of state-of-the-art questions of cement hydration including the influence of individual hydrate phases on the solidification process.
CRIS-Team Scopus Importer:2025-05-02
Keywords: Blended cement; Calcium-silicate-hydrate (C-S-H); Cement; Cement paste; Elastic moduli; Ettringite; Hydration; Microstructure; Modeling; Physical properties; Portland cement; Thermodynamic calculations

Der Jurensismergel von Mistelgau - Schulbert, Christian (Der Steinkern, 2013)
UnivIS-Import:2015-03-09:Pub.2013.nat.dgeo.IGM.LP.derjur
Keywords: Jurensismergel-Formation; Mistelgau

Describing Ammonoid Conchs - Klug, Christian; Korn, Dieter; Landman, Neil; Tanabe, Kazushige; de Baets, Kenneth; Naglik, Carole (Ammonoid Paleobiology: From anatomy to ecology, 2015)

Desmekalamos fuersichi nov. gen., nov. spec., ein Mikroröhrchen (Cyanophycee ?) aus den norischen Riffkalken des Taurus-Gebirges, Süd-Türkei - Senowbari-Daryan, Baba; Link, Michael (Beringeria, 2007)
Aus den norischen Riffschuttkalken des Taurus-Gebirges (Trias, Südtürkei) wird ein koloniebildendes Mikroröhrchen als Desmekalamos fuersichi nov. gen., nov. sp. beschrieben. Die Röhren rollen sich gesellig und irregulär verteilt um einen zentralen, sekundär mit Kalzit gefüllten Hohlraum auf. Durch die Bündelung der Röhrchen sowie durch biogen induzierte Aragonit-Nadeln um die einzelnen Mikroröhrchen herum entsteht eine größere, dickwandige und im Durchlicht dunkel erscheinende Makroröhre, die bevorzugt innerhalb mikrobieller Krusten im Riffbiotop auftritt. In der Wand der Makroröhre erscheinen die einzelnen Röhrchen von Desmekalamos fuersichi im Durchlicht meist als kleine, helle Punkte oder als kurze Schläuche, was mit Bohrungen von Mikroorganismen verwechselt werden kann. Die systematische Zuordnung von Desmekalamos fuersichi wird diskutiert. Höchstwahrscheinlich handelt sich hierbei um Cyanophyceen.
UnivIS-Import:2015-04-14:Pub.2007.nat.dgeo.IGM.LP.desmik
Keywords: Desmekalamos; Cyanophyta; Trias; Nor; Riff; Taurus-Gebirge; Türkei

Desmoinesian (Middle Pennsylvanian) orthocerid cephalopods from the Buckhorn Asphalt Lagerstätte in Oklahoma, Midcontinent North America - Niko, Shuji; Seuß, Barbara; Mapes, Royal H. (Paleontological Research, 2018)
UnivIS-Import:2017-01-09:Pub.2016.nat.dgeo.IGM.LP.bryozo
Keywords: Bryozoa; Oklahoma; Palaeoecology; Pennsylvanian; Preservation; Taxonomy

Desulphurisation, chromite alteration, and bulk rock PGE redistribution in massive chromitite due to hydrothermal overprint of the Panton Intrusion, east Kimberley, Western Australia - Beinlich, Andreas; von Heydebrand, Adrian; Klemd, Reiner; Martin, Laure; Hicks, John (Ore Geology Reviews, 2020)
The Central and Western Zones of the Halls Creek Orogen (HCO) of the East Kimberley region of Western Australia host various Paleoproterozoic layered mafic–ultramafic intrusions. The 1856 ± 2 Ma layered mafic–ultramafic Panton Intrusion of the Central Zone contains a reef-type platinum-group element (PGE) mineralisation associated with metamorphosed chromitite horizons. Here we investigate the compositional variation of chromite within the A chromitite layer, or Main Chromitite Layer (MCL), base metal sulphides (BMS), and the associated PGE distribution. Electron-microprobe analysis (EMPA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) data reveal complex chemical zoning of the chromite reflecting post-magmatic sub-solidus re-equilibration and fluid–rock interaction during metamorphism of the host rocks. The sulphur isotopic composition of the BMS (δ34S: −1.67 to 2.89‰) suggests negligible contamination of the parental melt by crustal sulphur and thus favours BMS formation due to fractional crystallisation. Furthermore, pentlandite compositions indicate the highest ƒS2 in the centre of the MCL, which coincides with a considerably heavier sulphur isotope composition compared to pentlandite in the surrounding ultramafic host rock. Alteration of the BMS during amphibolite facies hydration of the Panton Intrusion resulted in the formation of secondary bornite and digenite from the chalcopyrite as well as desulphurisation of pyrrhotite and pentlandite to secondary magnetite. The bulk rock PGE concentrations are controlled by the distribution of platinum-group minerals (PGM) due to the low PGE concentrations in BMS. PGM are present as inclusions in chromite, suggesting that they formed under sulphur-undersaturated conditions. Additional PGM are present within the interstitial serpentine-chlorite matrix suggesting that they precipitated during fluid-rock interaction and hydration of the silicate matrix. Likely sources for the remobilised PGE include PGM inclusions in altered rim zones of magmatic chromite and PGE released due to desulphurisation of BMS despite their low PGE concentrations.
CRIS-Team Scopus Importer:2020-02-04
Keywords: Base-metal sulphides; Chromitite reef; Desulphurisation; Hydrothermal alteration; Layered ultramafic intrusion; PGE deposit; PGE mobility; Serpentinisation

Detecting Groundwater Temperature Shifts of a Subsurface Urban Heat Island in SE Germany - Schweighofer, Julian; Wehrl, Michael; Baumgärtel, Sebastian; Rohn, Joachim (Water, 2021)
The subsurface beneath cities commonly shows a temperature anomaly, a so-called Subsurface Urban Heat Island (SUHI), due to anthropogenic heat input. This excess heat has multiple effects on groundwater and energy resources, such as groundwater chemistry or the efficiency of geothermal systems, which makes it necessary to investigate the temporal development of a SUHI. For this purpose, temperature profiles of 38 observation wells in the German city of Nuremberg were evaluated from 2015 to 2020 and the measured temperature changes were linked to the surface sealing. The results show that the groundwater temperatures changed between -0.02 K/a and +0.21 K/a, on average by +0.07 K/a during this period. A dependence between the temperature increase and the degree of sealing of the land surface was also observed. In areas with low surface sealing of up to 30% the warming amounts were 0.03 K/a on average, whereas in areas with high sealing of over 60% significantly higher temperature increases of 0.08 K/a on average were found. The results clearly emphasize that the subsurface urban heat island in its current state does not represent a completed process, but that more heat energy continues to enter the subsoil within the city than is the case with near-natural land surfaces.
CRIS-Team WoS Importer:2021-06-04

Detecting initial aragonite and calcite variations in limestone-marl alternations - Nohl, Theresa; Steinbauer, Manuel; Sinnesael, Matthias; Jarochowska, Emilia (Sedimentology, 2021)
Limestone-marl alternations are commonly used for high-resolution cyclostratigraphic studies and palaeoenvironmental reconstructions, but diagenetic studies indicate that not all limestone-marl alternations reflect genuine differences in the initial sediment composition driven by environmental changes. Differences in the ratios of diagenetically inert trace elements between limestones and marls indicate changes affecting the terrigenous fraction of the precursor sediment. Contrarily, limestone-marl alternations without these differences can be the product of: (i) variations in CaCO3 input (aragonite, calcite); (ii) distortion of the latter by diagenetic CaCO3 redistribution; or (iii) diagenetic CaCO3 redistribution in a homogeneous precursor sediment. The aim of this study is to provide a method to differentiate these cases and to identify variations in the proportion of calcite and aragonite in the precursor sediment composition. The model of differential diagenesis assumes that the concentration of diagenetically inert elements is inversely proportional to the amount of redistributed CaCO3. Consequently, the difference between ratios of diagenetically inert elements from two adjacent beds is a measure for CaCO3 redistribution. This is quantifiable by the vector length between ratios from two adjacent beds. The approach is illustrated here by evaluation of a case study from the Silurian of Gotland, Sweden. Trace elements were compared according to their solubility during diagenesis. All elements bound to clay minerals or calcite show similar patterns of vector length, while vector length of elements which fit into the aragonite lattice, and are diagenetically mobile, differ. The vector length approach provides a tool to test the diagenetic origin of limestone-marl alternations, to identify initial variations in CaCO3 input and to test a limestone-marl alternation's suitability for cyclostratigraphic analyses.
CRIS-Team WoS Importer:2021-06-04

Determination of effective flow properties of caprocks in the presence of multi-scale heterogeneous flow elements - Ma, Jingsheng; Drews, Michael; Kurtev, Kuncho; Aplin, Andrew (International Petroleum Technology Conference 2013: Challenging Technology and Economic Limits to Meet the Global Energy Demand, IPTC 2013, 2013)

Determination of fluid velocities in drinking water supply wells using bank filtration by means of stable isotope tracers - van Geldern, Robert; Kolb, Angela; Baier, Alfons; Barth, Johannes (Grundwasser, 2015)

Determination of ground thermal properties for energy piles by thermal response tests - Luo, Jin; Zhao, Haifeng; Huang, Wei; Zhu, Yongqiang; Xiang, Wei; Rohn, Joachim (Environmental Earth Sciences, 2018)
Keywords: Effective thermal conductivity; Energy pile; Borehole thermal resistance; Ground heat exchanger

Determination of the Concentration of Carbonic Species in Natural Waters: Results from a World-Wide Proficiency Test - Verma, Mahendra P.; Portugal, Enrique; Gangloff, Sophie; Aurora Armienta, Maria; Chandrasekharam, Dornadula; Sanchez, Mayela; Renderos, Roberto E.; Juanco, Miguel; van Geldern, Robert (Geostandards and Geoanalytical Research, 2015)
Keywords: Acid-base titration; Analytical method; CO2 chemistry; Interlaboratory comparison; Natural waters

Determination of the Temperature Development in a Borehole Heat Exchanger Field Using Distributed Temperature Sensing - Bertermann, David; Suft, Oliver (Energies, 2024)
The use of geothermal borehole heat exchangers (BHEs) in combination with ground-source heat pumps represents an important part of shallow geothermal energy production, which is already used worldwide and becoming more and more important. Different measurement techniques are available to examine a BHE field while it is in operation. In this study, a field with 54 BHEs up to a depth of 120 m below ground level was analyzed using fiber optic cables. A distributed temperature sensing (DTS) concept was developed by equipping several BHEs with dual-ended hybrid cables. The individual fiber optics were collected in a distributor shaft, and multiple measurements were carried out during active and inactive operation of the field. The field trial was carried out on a converted, partly retrofitted, residential complex, “Lagarde Campus”, in Bamberg, Upper Franconia, Germany. Groundwater and lithological changes are visible in the depth-resolved temperature profiles throughout the whole BHE field.
CRIS-Team Scopus Importer:2024-10-04
Keywords: borehole heat exchanger; distributed temperature sensing; fiber optics; shallow geothermal energy; temperature measurement

Determination of the thermal conductivity of sandstones from laboratory to field scale - Luo, Jin; Jia, Jia; Zhao, Haifeng; Zhu, Yongqiang; Guo, Qinghai; Cheng, Chaojie; Tan, Long; Xiang, Wei; Blum, Philipp; Rohn, Joachim (Environmental Earth Sciences, 2016)
Keywords: Laboratory measurements; Structure analysis; Thermal conductivity; Thermal response test (TRT); Wave velocity

Determining in situ pH values of pressurised fluids using stable carbon isotope techniques - Myrttinen, Anssi; Becker, V.; Mayer, B.; van Geldern, Robert; Barth, Johannes (Chemical Geology, 2015)

Detrital zircon U-Pb and Lu-Hf analysis of Paleozoic sedimentary rocks from the Pearya terrane and Ellesmerian Fold Belt (northern Ellesmere Island): A comparison with Circum-Arctic datasets and their implications on terrane tectonics - Malone, Shawn J.; Mcclelland, William C.; von Gosen, Werner; Piepjohn, Karsten (Circum-Arctic Structural Events: Tectonic Evolution of the Arctic Margins and Trans-Arctic Links with Adjacent Orogens, 2019)
Detrital zircon U-Pb and Hf isotopic data from Ordovician to Devonian-Carboniferous sedimentary rocks sampled from the Pearya terrane and adjacent areas, northern Ellesmere Island, record temporal variation in detrital zircon signature on the northeastern Arctic margin of Laurentia. Ordovician to Silurian clastic sediments deposited on the Pearya terrane record a provenance signal from before terrane accretion. This signal is dominated by Ordovician arc material and grains derived from recycling of Proterozoic metasedimentary and metaigneous basement. This pattern is similar to Neoproterozoic detrital zircon spectra from the Svalbard and East Greenland Caledonides, supporting the exotic nature of the Pearya terrane and links between Pearya and the Arctic Caledonides. Sedimentary rock deposited in the late Ordovician and early Silurian deep water basin of the Clements Markham fold belt likewise record a recycled source containing abundant early Neoproterozoic and Mesoproterozoic aged zircon. This contrasts with similarly aged units on Franklinian shelf, which contain much more abundant Paleoproterozoic zircon ages.
CRIS-Team WoS Importer:2019-11-15

Development of a Calculation Concept for Mapping Specific Heat Extraction for Very Shallow Geothermal Systems - Schwarz, Hans; Jocic, Nikola; Bertermann, David (Sustainability, 2022)
Horizontal shallow geothermal applications are easy to install, and their installation process is less liable to legislation than other geothermal systems. Due to a lack of planning guidance, the opportunity to implement such systems is often overlooked, although geothermal installations are urgently needed as a sustainable energy source. To give a foundation for including very shallow geothermal systems in local heat supply planning, potential maps are crucial. To enable their utilization in energy use plans or similar elaborations for municipalities, location-specific and system-specific heat extractions are required. Since applicable standards are not available, it is nearly impossible to provide aggregate propositions, which are essential for potential maps. In this study, a concept was evolved for deriving very shallow geothermal potential maps with location-specific and system-specific heat extraction values. As a basis, VDI 4640 Part 2 information regarding heat extraction and respective climate zone references was utilized. Furthermore, climate information and a soil map were needed to apply the concept to the study area. The application of the concept in an Austrian study area resulted in appropriate potential maps. Moreover, this concept is similarly applicable in other areas of interest.<br
Keywords: very shallow geothermal potential (vSGP); horizontal geothermal systems; heat extraction; potential maps; mapping concept; soil map; heating degree days (HDD); energy use plan

Development of magnetic fabrics during hydrothermal alteration in the Soultz-sous-Forêts granite from the EPS-1 borehole, Upper Rhine Graben - de Wall, Helga; et al. (2004)

Development of single-crystal σ-shaped quartz porphyroclasts by dissolution-precipitation creep in a calcite marble shear zone - Bestmann, Michel; et al. (Journal of Structural Geology, 2004)
Keywords: σ-Shape; Calcite marble; Cathodoluminescence; Dissolution-precipitation creep; Electron backscatter diffraction (EBSD); Porphyroclast; Quartz

Devonian climate and reef evolution: insights from oxygen isotopes in apatite. - Joachimski, Michael; Breisig, Stephan; Buggisch, Werner; Talent, John; Mawson, Ruth; Gereke, Manfred; Morrow, Jarred; Day, Jed; Weddige, Karsten (Earth and Planetary Science Letters, 2009)
Conodonts, microfossils composed of carbonate-fluor apatite, are abundant in Palaeozoic-Triassic sediments and have a high potential to preserve primary oxygen isotope signals. In order to reconstruct the palaeotemperature history of the Devonian, the oxygen isotope composition of apatite phosphate was measured on 639 conodont samples from sequences in Europe, North America and Australia. The Early Devonian (Lochkovian; 416-411 Myr) was characterized by warm tropical temperatures of around 30 °C. A cooling trend started in the Pragian (410 Myr) with intermediate temperatures around 23 to 25 °C reconstructed for the Middle Devonian (397-385 Myr). During the Frasnian (383-375 Myr), temperatures increased again with temperatures to 30 °C calculated for the Frasnian-Famennian transition (375 Myr). During the Famennian (375-359 Myr), surface water temperatures slightly decreased. Reconstructed Devonian palaeotemperatures do not support earlier views suggesting the Middle Devonian was a supergreenhouse interval, an interpretation based partly on the development of extensive tropical coral-stromatoporoid communities during the Middle Devonian. Instead, the Devonian palaeotemperature record suggests that Middle Devonian coral-stromatoporoid reefs flourished during cooler time intervals whereas microbial reefs dominated during the warm to very warm Early and Late Devonian. © 2009 Elsevier B.V. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2009.nat.dgeo.IGM.LG.devoni
Keywords: apatite; climate; Devonian; oxygen isotopes; reefs

Devonian paleoclimate and its drivers: A reassessment based on a new conodont δ18O record from South China - Chen, Bo; Ma, Xueping; Mills, Benjamin J.W.; Qie, Wenkun; Joachimski, Michael; Shen, Shuzhong; Wang, Chengyuan; Xu, Honghe; Wang, Xiangdong (Earth-Science Reviews, 2021)
A new Devonian oxygen isotope record based on 180 measurements of conodont apatite is reported from South China. The comparison with published Devonian δ18Oapatite data shows a considerable offset between records from different paleocontinents. This difference can be interpreted by regional variations in salinity, with the epicontinental seas having a distinctly lower salinity and δ18Oseawater than the open ocean due to the influence of fresh-water runoff. Our findings suggest that the oxygen isotope record from open ocean settings is the preferred archive for reconstructing the history of ocean temperature and/or ice volume over the Phanerozoic. Despite regional differences, the South China and European records show similar long-term trends characterized by a pronounced cooling during the Pragian to Eifelian followed by significant warming over the Eifelian/Givetian to Frasnian, and a further cooling starting in the Famennian, accelerating in the earliest Carboniferous. The Early Devonian cooling coincided with early vascular plant root − soil interactions and a significant diversity increase in both spores and megaplant fossils, suggesting that the rise of rooted vascular plants may have played a key role in triggering climate cooling. Subsequent climatic warming over the Middle to Late Devonian transition may have been linked to metamorphic CO2 input from the Acadian Orogeny, while Famennian cooling occurred in a context of exposure and weathering of basalts and ophiolites and coincided with the advent of seed plants. We conclude that climate changes during the Devonian were likely driven by a combination of plant evolutionary advances and changes in tectonics. We further test these interpretations by running the COPSE (Carbon, Oxygen, Phosphorus, Sulfur and Evolution) biogeochemical model. The model prediction is capable of reproducing the pCO2 record under these scenarios, although the model is not capable of reproducing the degree of temperature variation, likely due to its simplicity.
Keywords: Paleotemperatures; Vascular vegetation; Acadian Orogeny; Volcanism; Regional δ18O difference

Devonian pearls and ammonoid-endoparasite co-evolution - de Baets, Kenneth; Klug, Christian; Korn, Dieter (Acta Palaeontologica Polonica, 2011)
Raised shell projections on the inner shell walls that form pits on the internal moulds of Devonian ammonoids have been known for several decades. New specimens from Morocco reveal novel details or these structures; most, if not all, of which consist of a capsule of ammonoid shell that covers tiny tubes attached to the outer (= lateral or ventral) shell wall from the inside. In accordance with comparable Recent occurrences of similar structures in molluscs, we use the term "pearls" for these structures and the pits they form on the internal moulds. The nature of these encapsulated tubes is described and discussed. Because of the presence of these tubes inside the pearls, pearl arrangement, and their similarity to Recent mollusc occurrences, the tubes are interpreted as traces of parasitoses. The pearls and pits were grouped into five types based on differences in morphology, size, and arrangement. Then, having used these traits to perform a simple cladistic analysis, the resulting cladogram was compared to the phylogeny of ammonoids. Based on this comparison, it appears likely that the parasites underwent a co-evolution with the ammonoids, which lasted 10 to 15 Ma. Patterns of evolutionary events include co-speciation, "drowning on arrival" (end of parasite lineage near base of a new host clade), and "missing the boat" (parasite lineage does not adapt to a new host clade, thus not evolving a new parasite clade). Because of the lack of fossilised soft tissue, only speculations can be made about the systematic affiliation of the parasites, their life-cycle, infection strategy, and ecological framework. Some co-occurring bivalves also have pits reminiscent to structures caused by trematodes in Recent forms. Based on the available information, the tubes are interpreted as artefacts of trematode infestations, which, if correct, would extend the fossil record of parasitic trematodes into the Early Devonian.
Keywords: Ammonoidea; Trematoda; parasite; pearl; co-evolution; Devonian; Morocco; Algeria; Germany

Diagenesis and petrophysics of regional sandstone suites in Southern Apennines Foreland Basin, Italy - Civitelli, Massimo; Borrelli, Mario; Criniti, Sara; Ravidà, Domenico; Falsetta, Ettore (Rendiconti Online Societa Geologica Italiana, 2023)
The southern Apennines foreland region preserves deep-marine turbiditic clastic wedges with contrasting and mixed petrofacies, including 5 distinctive sandstone suites: I) quartzarenite suite of the Numidian Sandstone, II) quartzolithic sandstone suite of the Corleto Perticara Formation, III) quartzofeldspatolithic sandstone suite of the Cilento Group (San Mauro and Albidona Formations), IV) quartzofeldspathic suite of the Gorgoglione Formation, V) arkose sandstone suite of the Oriolo, Nocara, Castelvetere formations. Since the great complexity of these sediments, the main diagenetic events and the key petrophysical properties were investigated to update a database that could be an effective method for petrophysical parameters prediction for similar foreland petroleum systems. The most widespread diagenetic minerals are carbonate, mainly calcite and dolomite, occurring as replacement on detrital grains or as pore-filling cements, and less quartz, phyllosilicate and Fe-oxides and hydroxides cements. These minerals accounted for a widespread process of cementation that, together with compaction greatly influenced the sandstone suites petrophysics, from the lowest porosity median value (3.2 %) of the Numidian Sandstone to the highest value of the Oriolo Fm. (16,75 %). In fact, these formations show porosity and permeability values depending by detrital modes that control the effect of compaction, cementation and dissolution during diagenesis.
CRIS-Team WoS Importer:2023-04-14

Diagenesis makes the impossible come true: intersecting beds in calcareous turbidites - Westphal, Hildegard; Lavi, Jonathan; Munnecke, Axel (Facies, 2015)
Constructing a time-frame of the past is fundamental for any geological interpretation, and the recognition of orbital cycles preserved in the stratigraphic record has revolutionized our understanding of the global timescale, especially for the Cenozoic. In the past decades, astrochronological and cyclostratigraphic approaches based on Milankovitch cycles have become a widely used tool for precisely dating stratigraphic boundaries by calibrating sedimentary units with astronomically tuned timescales. In many cases, strikingly rhythmic limestone-marl alternations are used for such approaches. Astrochronological approaches as a basic principle rely on the fundamental assumption that such rhythmites reflect fluctuating environmental conditions caused by variations in incident solar radiation such as changes in sea level, temperature, or weathering. Nevertheless, in many cases, the crucial question as to whether such rhythmites represent primary cycles or are purely of diagenetic origin has never been positively decided. In those cases, stratigraphic dating with this method is left unreliable. Here, the ability of diagenesis to produce rhythmic bedding lacking any relation to primary sedimentary signals is demonstrated. The Miocene succession discussed here shows two cemented sets of beds with different inclinations, one parallel to the sedimentary layering, the other, coeval, but in an oblique direction. These two sets merge and do not show distinct boundaries, thus indicating synchronous cementation. It is interpreted that minor early synsedimentary tectonic stress introduced an oblique anisotropy. During early differential diagenesis, this dual anisotropy influenced the geometry of the cemented layers, giving the impression of intersecting layers.
Keywords: Astrochronology; Diagenesis; Limestone-marl alternations; Miocene; Stratigraphy; Turbidites

Diagenesis of plattenkalk: Examples from the Solnhofen area (Upper Jurassic, southern Germany) - Munnecke, Axel; Westphal, Hildegard; Kölbl-Ebert, Martina (Sedimentology, 2008)
The Upper Jurassic (Tithonian) plattenkalk successions in the Solnhofen/ Eichstätt area consist of alternations of thin-bedded, laminated, fine-grained, very pure limestones (so-called 'flinz beds') and softer interlayers with slightly lower carbonate contents that are also laminated and show a foliaceous weathering appearance ('fäule beds'). These successions are world famous for their exceptionally well-preserved fossils. In contrast to the well-studied wealth of fossils, little is known about the origin and diagenesis of the host rock. The reason for this discrepancy might lay in the monotonous appearance of these fine-grained mudstones that require electron microscopical examination. Study of samples from the Solnhofen-Eichstädt area implies that flinz and fäule beds have undergone differential diagenesis. The ultrastructure of the flinz beds is characterized by interlocking microspar crystals, whereas the fäule beds show smaller and less interlocking crystals. The ratios of diagenetically inert trace elements lack clear differences between the two interlayered lithologies. While most authors agree that the flinz-fäule rhythm reflects rhythmically changing environmental conditions, primary rhythms can be taken as proven only where statistically significant differences in diagenetically resistant proxies are found. The absence of clear primary differences between flinz and fäule beds, however, leaves the question of primary differences unsolved. It is concluded that diagenesis has had a strong influence on the genesis of the lithological rhythm, and that any primary rhythm underlying the diagenetically mature rhythm is less clear than generally assumed. © Journal compilation © 2008 International Association of Sedimentologist
Keywords: Upper Jurassic; Tithonian; Plattenkalk; Solnhofen; Diagenesis

Diagenesis of Upper Jurassic concretions from the Antarctic Peninsula - Kießling, Wolfgang; et al. (Journal of Sedimentary Research, 2001)
Early-diagenetic calcite concretions are widespread in mudstone-tuff sequences deposited in Late Jurassic oxygen-deficient basins of the Antarctic Peninsula. Although obscured or destroyed in host rocks, original components and sedimentary structures are well preserved in concretions, in spite of significant mineralogical and geochcmical change during growth. Early diagenesis led to a rapid and almost total variation in the mineralogy within the concretions, independently of the original host lithologies. Siliceous particles were replaced by chlorite and zeolites in suboxic, alkaline, and moderately reducing conditions on the sea floor and in the first centimeters of burial. These conditions also led to localized early formation of phosphate concretions. Pyrite developed subsequently because of high sulfide abundance in the sulfate reduction zone. Most calcite precipitation took place in the lower part of the sulfate reduction zone in a strongly alkaline environment where sulfide content had been lowered by pyrite precipitation. In this stage, the remaining siliceous elements were dissolved or replaced by calcite. Later diagenetic changes include enlargement of zeolites, minor changes in clay minerals, and the formation of calcite veins. The wide range of δ 13C values in cement and vein calcite (-1.4‰ and -20.23‰ PDB) is explained by mixed carbon sources from organic matter oxidation and dissolution of calcareous shells. The low δ 18O of calcite (-2.34‰ to -19.72‰ PDB) is the result of recrystallization in contact with high-temperature diagenetic or hydrothermal fluids flushed through micro-fractures in the concretions, which also produced extensive vein formation. Copyright © 2001, SEPM (Society for Sedimentary Geology).
UnivIS-Import:2015-03-09:Pub.2001.nat.dgeo.IGM.LP.diagen

Diagenetic alteration of the structure and d18O signature of Palaeozoic ichthyolith and conodont apatite: potential use for corrected isotope signatures in palaeoenvironmental interpretation. - Barham, Milo; Joachimski, Michael; Murray, J.; Williams, D. M. (Chemical Geology, 2012)
UnivIS-Import:2015-03-09:Pub.2012.nat.dgeo.IGM.LG.diagen

Diagenetic constraints on heterogeneous reservoir quality assessment: A Triassic outcrop analog of meandering fluvial reservoirs - Caracciolo, Luca; et al. (Aapg Bulletin, 2016)
Reliable modeling of meandering fluvial reservoirs is challenging because of the heterogeneity in magnitude and pattern of porosity and permeability related to depositional and diagenetic features. Early mechanical and chemical alterations proceed along different pathways directly related to depositionally governed differences in textural and compositional parameters. In a well-constrained sedimentological framework and with relatively homogeneous conditions of detrital composition, this study aims to determine the effect of depositional fabric on early diagenetic processes and their collective effect on petrophysical properties (pore size distribution, open porosity, and permeability). A high-resolution qualitative and quantitative petrographic analysis is conducted on 22 fine-to very fine-grained sandstones from the main meandering fluvial facies of the channel (center and margin), point bar (lower, middle, and upper), scroll bar, and chute channel of a Triassic outcrop analog. The occurrence of small-scale internal heterogeneity associated with detrital matrix and suspension settling laminae favors the compaction process and hinders early pore-filling cement precipitation that helps the preservation of primary porosity. Multivariate statistical treatment of data demonstrates that large (>1 mu m) and well-connected primary inter granular pores are the main contributors to permeability in the more heterogeneous samples. The distribution of the finer-grained sediment fraction is strongly facies related as a result of hydraulic sorting. Better understanding of linkages between depositionally predictable features and diagenetically induced heterogeneity may lead to realistic reservoir models and enhanced effectiveness of exploitation and bypassed-oil recovery strategies.

Diagnostic characteristics and paleodynamics of supraglacial rock avalanches, Innerdalen, Western Norway - Schleier, Markus; Hermanns, Reginald L.; Gosse, John C.; Rohn, Joachim (Geomorphology, 2015)
Keywords: 10Be surface-exposure dating; DAN3D; Numerical runout modeling; Paleoenvironmental conditions; Rock avalanche; Supraglacial debris

Dickenzuwachs der exotischen Thuja plicata und der einheimischen Picea abies in Ab-hängigkeit von Klima und Witterung in Süddeutschland - Schlüter, Rebecca; Steinbauer, Manuel; Remmele, Sabine; Aas, Gregor (Allgemeine Forst- und Jagdzeitung, 2015)

Did climate changes trigger the Late Devonian Kellwasser Crisis? Evidence from a high-resolution conodont δ18OPO4 record from South China - Huang, Cheng; Joachimski, Michael; Gong, Yiming (Earth and Planetary Science Letters, 2018)
Keywords: Devonian; oxygen isotope; conodont; palaeotemperature; South China

Did intense volcanism trigger the first Late Ordovician icehouse? REPLY. - Buggisch, Werner; Joachimski, Michael; Lehnert, Oliver; Bergström, Stig M.; Repetski, John E. (Geology, 2011)
UnivIS-Import:2015-03-09:Pub.2011.nat.dgeo.IGM.LG.didint

Did intense volcanism trigger the first Ordovician icehouse? - Buggisch, Werner; Joachimski, Michael; Lehnert, Oliver; Bergström, Stig M.; Repetski, John E.; Webers, Gerald F. (Geology, 2010)
UnivIS-Import:2015-03-09:Pub.2010.nat.dgeo.IGM.LG.didint

Did plankton evolution trigger the Ordovician diversifications? - Lehnert, Oliver; Vecoli, Marco; Servais, Thomas; Nützel, Alexander (Acta Palaeontologica Sinica, 2007)
UnivIS-Import:2015-03-09:Pub.2007.nat.dgeo.IGM.LG.didpla

Die Ammonitenfauna und Stratigraphie der Tongrube Mistelgau bei Bayreuth (Oberfranken) - Schulbert, Christian (Berichte der Naturwissenschaftlichen Gesellschaft Bayreuth, 2001)
UnivIS-Import:2015-03-09:Pub.2001.nat.dgeo.IGM.LP.dieamm

Die Anisotropie der magnetischen Suszeptibilität eine Methode zur Gefügeanalyse - de Wall, Helga (Zeitschrift der Deutschen Gesellschaft für Geowissenschaften, 2005)
UnivIS-Import:2015-03-09:Pub.2005.nat.dgeo.IGM.c3tekt.dieani

Die Bedeutung der Conodontenstratigraphie in der Klastenforschung am Beispiel der Tertiärabfolgen von Ellesmere Island (kanadische Arktis). - Lehnert, Oliver; Nowlan, Godfrey; Lee, Carmen (Archiv für Geschiebekunde, 2004)
UnivIS-Import:2015-03-09:Pub.2004.nat.dgeo.IGM.LG.diebed

Die Bedeutung der Geologie und Mineralogie im geplanten Wissenschaftsmuseum Erlangen - Leiste, Volker; Baier, Alfons; Tobschall, Heinz-Jürgen; Göbbels, Matthias (Geologische Blätter für Nordost-Bayern und angrenzende Gebiete, 1999)
UnivIS-Import:2015-03-05:Pub.1999.nat.dgeo.IGM.LAG.diebed

Die Eklogite des Erzgebirges. Freiberger Forschungsheft C 456. - Schmädicke, Esther (Deutscher Verlag für Grundstoffindustrie, 1994)
UnivIS-Import:2017-03-24:Pub.1994.nat.dgeo.IGM.legeo.dieekl

Die fossile Burggrabenhöhle und ihr Aragonitvorkommen auf dem Wolfstein, Neumarkt in der Oberpfalz, Bayern - Leja, Ferdinand; Knolle, Friedhart; López Correa, Matthias (Mitteilungen des Verbandes der Deutschen Höhlen- und Karstforscher, 2024)
Archaeological examinations of the castle Wolfstein above the village Neumarkt in der Oberpfalz in Bavaria (Germany) led to the rediscovery of Europe’s largest aragonite deposit within the sediment-filled cave ruin Burggrabenhöhle. The massive aragonitic speleothems had been used in large quantities to build the castle walls. This peculiar deposit was examined and presented to the public in an exhibition.
CRIS-Team Scopus Importer:2025-02-04

Die fossile Burggrabenhöhle und ihr Aragonitvorkommen auf dem Wolfstein, Neumarkt in der Oberpfalz, Bayern - Leja, Ferdinand; Knolle, Friedhart; López Correa, Matthias (Mitteilungen - Verbandes der Deutschen Hohlen- und Karstforscher, 2024)
Archaeological examinations of the castle Wolfstein above the village Neumarkt in der Oberpfalz in Bavaria (Germany) led to the rediscovery of Europe’s largest aragonite deposit within the sediment-filled cave ruin Burggrabenhöhle. The massive aragonitic speleothems had been used in large quantities to build the castle walls. This peculiar deposit was examined and presented to the public in an exhibition.
CRIS-Team Scopus Importer:2024-10-25

Die moderne Computer-Tomographie (Modell v|tome|x s 240 von GE/Phoenix) am Lehrstuhl für Paläoumwelt (GZN, Erlangen) – Methodik und Anwendungsbeispiele - Schulbert, Christian; Koch, Roman (Geologische Blätter für Nordost-Bayern und angrenzende Gebiete, 2017)
Keywords: Mikro-Computer-Tomographie

Die Palökologie des Gastropoden Coelodiscus minutus aus dem Posidonienschiefer - Teichert, Sebastian; Nützel, Alexander (Jahrestagung der Paläontologischen Gesellschaft 2008, 2008)
UnivIS-Import:2015-04-16:Pub.2008.nat.dgeo.IGM.LP.diepal

Die Tongrube Mistelgau bei Bayreuth - Schulbert, Christian (Erdgeschichtliche Zeitreise durch Nordbayern, 2007)
UnivIS-Import:2015-04-20:Pub.2007.nat.dgeo.IGM.LP.dieton
Keywords: Tongrube; Mistelgau

Die Tongrube Mistelgau - Schulbert, Christian (Der Steinkern, 2013)
UnivIS-Import:2015-03-09:Pub.2013.nat.dgeo.IGM.LP.dieton
Keywords: Tongrube; Mistelgau

Differences in natural gamma radiation characteristics of Erinpura and Malani granites in NW India - Scharfenberg, Lars; Jandausch, Sebastian; Anetzberger, Lina; Regelous, Anette; Sharma, Kamal K.; de Wall, Helga (Journal of Earth System Science, 2019)
In NW India, large volumes of exposed Neoproterozoic basement rocks are formed by two magmatic suites, Erinpura granites as a late thermal event with respect to the ∼ 1 Ga Delhi Orogeny and the younger Malani igneous suite (770–750 Ma). Average uranium and thorium equivalent concentrations (in ppm) inferred from spectroscopic gamma radiation survey are higher in Malani rocks (Th 47.33 ppm and U 6.95 ppm) as compared to the Erinpura granites (Th 33.55 ppm and U 4.77 ppm). These values are considerably above the granite world average (Th 14.8 ± 13.2 ppm; U 3.93 ± 3.27 ppm). High U (up to 19 ppm) and Th (up to 88 ppm) in some Malani granites and a constant Th–U ratio of 7 points to a high degree of fractionation of the felsic magma. Higher radioelement concentration in the east (Mirpur granite) as compared to the west (Jaswantpura granite) is substantiated by geochemical data. Areas to the west and east of the Sirohi frontal thrust show differences, most likely a consequence of anatexis in the eastern sector. A high linear correlation between inductively coupled plasma mass spectrometry and gamma-ray data underlines the suitability of in-situ measurements for the determination of U and Th concentrations during a field survey providing basic information for future petrogenetic and risk-hazard studies in this granitic terrain.
CRIS-Team Scopus Importer:2019-05-28
Keywords: granitoids; Natural gamma radiation; NW India; thorium; uranium

Different carbon reservoirs of auriferous fluids in African Archean and Proterozoic gold deposits? Constraints from stable carbon isotopic compositions of quartz-hosted CO2-rich fluid inclusions - Lüders, Volker; Klemd, Reiner; Oberthür, Thomas; Plessen, Birgit (Mineralium Deposita, 2015)
Stable carbon (and when present, nitrogen) isotope ratios of fluid inclusions in quartz from selected gold deposits in Ghana and Zimbabwe have been analyzed using a crushing device interfaced to an isotopic ratio mass spectrometer (IRMS) in order to constrain possible sources of the auriferous fluids. The study revealed a striking difference in stable carbon isotopic compositions of CO2 in quartz-hosted fluid inclusions from Archean and Paleoproterozoic orogenic gold deposits and points to diverse sources of CO2 in the studied deposits. Whether this finding can be generalized for other Archean and Proterozoic orogenic gold deposits worldwide remains open. However, a significant CO2 contribution by mantle degassing can be ruled out for every deposit studied. Devolatilization of greenstone belt rocks is the most likely source for CO2 in some Archean Au deposits in Zimbabwe, whereas CO2 in Proterozoic vein-type Au deposits in the West African Craton is most likely derived from Corg-bearing metasedimentary rocks. The δ13CCO2 values of high-density CO2-rich, water-poor inclusions hosted in quartz pebbles from the world-class Au-bearing conglomerate deposits at Tarkwa (Ghana) differ considerably from the δ13CCO2 values of similar high-density CO2-rich inclusions in vein quartz from the giant Ashanti deposit (Ghana) and disprove the idea of derivation of the Tarkwaian quartz (and gold?) from an older equivalent to the Ashanti vein-type gold deposit.<br
Keywords: Gold; Africa; Fluid inclusions; Carbon isotopes; Nitrogen isotopes

Differential niche dynamics among major marine invertebrate clades - Hopkins, Melanie; Simpson, Carl; Kießling, Wolfgang (Ecology Letters, 2014)
The degree to which organisms retain their environmental preferences is of utmost importance in predicting their fate in a world of rapid climate change. Notably, marine invertebrates frequently show strong affinities for either carbonate or terrigenous clastic environments. This affinity is due to characteristics of the sediments as well as correlated environmental factors. We assessed the conservatism of substrate affinities of marine invertebrates over geological timescales, and found that niche conservatism is prevalent in the oceans, and largely determined by the strength of initial habitat preference. There is substantial variation in niche conservatism among major clades with corals and sponges being among the most conservative. Time-series analysis suggests that niche conservatism is enhanced during times of elevated nutrient flux, whereas niche evolution tends to occur after mass extinctions. Niche evolution is not necessarily elevated in genera exhibiting higher turnover in species composition. © 2013 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.
UnivIS-Import:2015-03-09:Pub.2014.nat.dgeo.IGM.LP.differ
Keywords: Carbonate environments; Climate change; Niche conservatism; Species turnover; Substrate affinity; Terrigenous clastic environments

Different magma differentiation processes of post-onset collision adakitic rocks in the Gangdese Batholith: Evidence from zircon trace elements - Lu, Tian Yu; He, Zhen Yu; Klemd, Reiner (Chemical Geology, 2023)
The widespread adakitic magmatism in southern Tibet, which postdates the onset of the India-Eurasia collision, is usually considered to be derived from the partial melting of Lhasa thickened lower crust. However, less attention has been paid to the magma differentiation processes following the formation of the parental adakitic melts. Here, we use in situ zircon trace-element geochemistry, combined with whole-rock geochemical data, to gain insight into the magma differentiation and related mineralization of two phases of post-onset collision adakitic magmatism from the Nyemo location in the southern Lhasa subterrane. Systematic variations in zircon trace-element compositions record fractional crystallization of specific minerals (e.g., titanite, magnetite) for the ca. 30 Ma monzogranite and equilibrium crystallization for the ca. 15 Ma granodiorite. This is also supported by thermodynamic modeling, which revealed that the monzogranite and granodiorite magmas underwent weak differentiation (melt fraction up to ∼70%) or no differentiation, respectively. Progressively reduced oxygen fugacity conditions during magnetite fractionation in the monzogranitic magmas resulted in sulfide segregation, thereby removing sulfur and chalcophile elements such as Ni and Cu from the melt. Thus, we propose on the basis of in situ zircon trace-element geochemistry that magnetite fractionation within shallow to mid-continental crust may lead to the low Cu fertility of magmas, forming some of the Cu-poor post-onset collision adakitic rocks in the Gangdese magmatic belt.
CRIS-Team Scopus Importer:2023-02-10
Keywords: Adakitic rock; Fractionation; Rhyolite-MELTS simulation; Tibet; Zircon geochemistry

Digesting the data - Effects of predator ingestion on the oxygen isotopic signature of micro-mammal teeth - Barham, Milo; Blyth, Alison J.; Wallwork, Melinda D.; Joachimski, Michael; Martin, Laure; Evans, Noreen J.; Laming, Belinda; McDonald, Bradley J. (Quaternary Science Reviews, 2017)
Keywords: Alteration; Cenozoic; Dentine; Digestion; Enamel; Palaeoclimatology; Palaeoenvironmental proxy; Predation; Stable isotopes; Trace elements

Digging deeper into colonial palaeontological practices in modern day Mexico and Brazil - Cisneros, Juan; Raja Schoob, Nussaibah Begum; Ghilardi, Aline Marcele; Dunne, Emma; Pinheiro, Felipe; Regalado Fernández, Omar Rafael; Sales, Marcos; Rodríguez-de la Rosa, Rubén; Miranda-Martínez, Adriana; González-Mora, Sergio; Bantim, Renan; de Lima, Flaviana; et al. (Royal Society Open Science, 2022)
Scientific practices stemming from colonialism, whereby middle- and low-income countries supply data for high-income countries and the contributions of local expertise are devalued, are still prevalent today in the field of palaeontology. In response to these unjust practices, countries such as Mexico and Brazil adopted protective laws and regulations during the twentieth century to preserve their palaeontological heritage. However, scientific colonialism is still reflected in many publications describing fossil specimens recovered from these countries. Here, we present examples of ‘palaeontological colonialism’ from publications on Jurassic–Cretaceous fossils from NE Mexico and NE Brazil spanning the last three decades. Common issues that we identified in these publications are the absence of both fieldwork and export permit declarations and the lack of local experts among authorships. In Mexico, access to many fossil specimens is restricted on account of these specimens being housed in private collections, whereas a high number of studies on Brazilian fossils are based on specimens illegally reposited in foreign collections, particularly in Germany and Japan. Finally, we outline and discuss the wider academic and social impacts of these research practices, and propose exhaustive recommendations to scientists, journals, museums, research institutions and government and funding agencies in order to overcome these practices.<br

Digital outcrop models as input for geostatistical fracture networks simulations - Drews, Michael; Deckert, Hagen (Society of Petroleum Engineers, 2011)

Digital skull anatomy of the Oligocene North American tortoise Stylemys nebrascensis with taxonomic comments on the species and comparisons with extant testudinids of the Gopherus–Manouria clade - Evers, Serjoscha W.; Al Lawati, Zahra (Swiss Journal of Palaeontology, 2024)
The anatomy of North American tortoises is poorly understood, despite a rich fossil record from the Eocene and younger strata. Stylemys nebrascensis is a particularly noteworthy turtle in this regard, as hundreds of specimens are known from Oligocene deposits, and as this species is one of the earliest fossil turtles to have been described in the scientific literature. Since its initial description based on a shell, many specimens with more complete material have been referred to Stylemys nebrascensis. Here, we review and confirm the referral of an important historic specimen to Stylemys nebrascensis, which includes shell, non-shell postcranial, and skull material. This allows us to document unique skull features of Stylemys nebrascensis (e.g., an unusual ‘poststapedial canal’ that connects the posterior skull surface with the cavum acustico-jugulare) and to refer another well-preserved skull to the species. Based on computed-tomography scanning of these two skulls, we provide a detailed description of the cranial and mandibular osteology of Stylemys nebrascensis. Stylemys nebrascensis has a combination of plesiomorphic skull characteristics (e.g., retention of a medial jugal process) and derived traits shared with extant gopher tortoises (e.g., median premaxillary ridge) that suggest it may be a stem-representative of the gopher tortoise lineage. This supports the hypothesis that extant and fossil tortoises from North America form a geographically restricted clade that split from Asian relatives during the Paleogene.
CRIS-Team Scopus Importer:2024-03-15
Keywords: Cranial evolution; Digital anatomy; Systematics; Taxonomy; Testudinidae; Tortoises; Turtles

Diking, young volcanism and diffuse hydrothermal activity on the southern Mid-Atlantic Ridge: the Lilliput field at 9°33S. - Haase, Karsten; Koschinsky, Andrea; Fretzdorff, Susanne; Petersen, Sven; Stecher, Jens; Seifert, Richard; Paulick, Holger; Giere, Olav (Marine Geology, 2009)
Detailed exploration with remotely operated and autonomous deep submergence vehicles has revealed, at 9°33′S, the presence of the southernmost active hydrothermal field known so far on the Mid-Atlantic Ridge. The size of the hydrothermal field, which we have named "Lilliput", is about 1000 m × 250 m. It lies in a water depth of 1500 m on a ridge segment (Segment A3) with considerably thickened crust of 11 km. Four relatively small diffuse vent sites occur on a large young (estimated < 100 years old) lava flow, partly covering the flow with hydrothermal Fe-oxide/hydroxide sediments. Based on homogeneous major element compositions of ca. 25 lava samples, this flow covers an area of at least 5 km × 0.6 km. The lava flow erupted from a series of parallel fissures at the western edge of the flow and a volcanic ridge consisting of up to 30 m high pillow mounds. The volcanic ridge probably represents the surface expression of an underlying dike which fed the flow. Several drained lava pond structures were observed within the flow but only one shows hydrothermal activity. The hydrothermal venting and precipitation of abundant Fe-oxyhydroxides appear to be related to the young diking and eruption event and the four different hydrothermally active sites of the Lilliput field lie along and almost equidistant from the eastern flank of the supposed dike. Although a hydrothermal plume some 500 m above the seafloor was found in two consecutive years (2005 and 2006), no high-temperature venting associated with Lilliput has been found, in agreement with findings at other ridges with thick crust such as Reykjanes. High magma supply rate and frequent diking and eruption events may lead to hot hydrothermal vents being rare in slow-spreading segments with thick crust whereas diffuse venting is abundant. Interestingly, the fauna at the Lilliput vents largely consists of small and apparently juvenile mussels (Bathymodiolus sp.) and did not show any signs of growth during the four years of continuing observations possibly reflecting pulsing hydrothermal activity. © 2009 Elsevier B.V. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2009.nat.dgeo.IGM.legeo.diking
Keywords: basalt; South Atlantic; Spreading Centre; vent fauna

Direct mapping of microscopic polarization in ferroelectric x(BiScO3)-(1-x)(PbTiO3) throughout its morphotropic phase boundary - Datta, Kaustuv; Richter, Andreas; Göbbels, Matthias; Keen, David A.; Neder, Reinhard (Physical Review B - Condensed Matter and Materials Physics, 2016)
Pair distribution functions of ferroelectric xBiScO3-(1-x)PbTiO3, obtained from neutron total scattering data, were examined and modeled utilizing the reverse Monte Carlo technique to depict exclusively the local structure of this compound throughout its reported morphotropic phase boundary (MPB). Microscopic polarizations due to the cation shifts have been mapped out from the refined crystal structure as a function of composition in order to reveal individual cation behavior driven by the composition. Direct evidences are provided for large static displacements of the cations (∼0.2-0.5Å), local cation ordering between Ti and Sc, and a categorical change of favored polarization directions of the cations at the conjuncture of the MPB. Apart from Sc, all cations have demonstrated an apparent transition from a relatively defined directional distribution to a broad and random distribution at x=xMPB, suggesting a flattening of the local potential function for them. These features can further be correlated with the general concept of structural instability of a ferroelectric system at the MPB, which is often linked to the manifestation of enhanced physical properties.

Direct oxygen isotope effect identifies the rate-determining step of electrocatalytic OER at an oxidic surface - Haschke, Sandra; Mader, Michael; Schlicht, Stefanie; Roberts, André Michael; Angeles-Boza, Alfredo; Barth, Johannes; Bachmann, Julien (Nature Communications, 2018)
Understanding the mechanism of water oxidation to dioxygen represents the bottleneck towards the design of efficient energy storage schemes based on water splitting. The investigation of kinetic isotope effects has long been established for mechanistic studies of various such reactions. However, so far natural isotope abundance determination of O-2 produced at solid electrode surfaces has not been applied. Here, we demonstrate that such measurements are possible. Moreover, they are experimentally simple and sufficiently accurate to observe significant effects. Our measured kinetic isotope effects depend strongly on the electrode material and on the applied electrode potential. They suggest that in the case of iron oxide as the electrode material, the oxygen evolution reaction occurs via a rate-determining O-O bond formation via nucleophilic water attack on a ferryl unit.