14C and δ13C characteristics of organic matter and carbonate in saltmarsh sediments from south west Scotland - Barth, Johannes; et al. (Journal of Environmental Monitoring, 2004)

210Pb-226 Ra disequilibria in young gas-laden magmas - Reagan, Mark; Turner, Simon; Handley, Heather; Turner, Michael; Beier, Christoph; Caulfield, John; Peate, David (Scientific Reports, 2017)

230Th-238U disequilibrium in East Scotia back-arc basalts: implications for slab contributions - Fretzdorff, Susanne; Haase, Karsten; Leat, Phil; Livermore, Roy; Garbe-Schönberg, Dieter; Fietzke, Jan; Stoffers, Peter (Geology, 2003)
UnivIS-Import:2015-03-09:Pub.2003.nat.dgeo.IGM.legeo.230th2

3D-Analysis of a non-planispiral ammonoid from the Hunsruck Slate: natural or pathological variation? - Stilkerich, Julia; de Baets, Kenneth; Smrecak, Trisha A. (PeerJ, 2017)
We herein examine the only known non-planispirally coiled early Devonian ammonoid, the holotype specimen of Ivoites opitzi, to investigate if the host was encrusted in vivo and if these sclerobionts were responsible for the trochospiral coiling observed in this unique specimen. To test if the presence of runner-like sclerobionts infested the historically collected specimen of Ivoites opitzi during its life, we used microCT to produce a three-dimensional model of the surface of the specimen. Our results indicate that sclerobionts grew across the outer rim (venter) on both sides of the ammonoid conch at exactly the location where the deviation from the planispiral was recognized, and where subsequent ammonoid growth would likely preclude encrustation. This indicates in vivo encrustation of the I. opitzi specimen, and represents the earliest documentation of the phenomenon. Further, this suggests that non-planispiral coiling in I. opitzi was likely pathologically induced and does not represent natural morphological variation in the species. Despite the observed anomalies in coiling, the specimen reached adulthood and retains important identifying morphological features, suggesting the ammonoid was minimally impacted by encrustation in life. As such, appointing a new type specimen-as suggested by some authors-for the species is not necessary. In addition, we identify the sclerobionts responsible for modifying the coiling of this specimen as hederelloids, a peculiar group of sclerobionts likely related to phoronids. Hederelloids in the Devonian are commonly found encrusting on fossils collected in moderately deep environments within the photic zone and are rarely documented in dysphotic and aphotic samples. This indicates that when the ammonoid was encrusted it lived within the euphotic zone and supports the latest interpretations of the Hunsrck Slate depositional environment in the Bundenbach-Gemunden area.
Keywords: Epicole; Pathology; Computed tomography; Hederelloidea; Ammonoidea; Epizoa; Heteromorph; Three-dimensional reconstruction; CT scan; Intraspecific variation

3D Joint Density Mapping - Drews, Michael (Conference Proceedings, 2008)

3D-Modellierung der Dogger-Malm Grenze im Raum Bad Staffelstein, abgeleitet aus Lineamentanalyse und Strukturkarte - Wehrl, Michael; Rohn, Joachim; de Wall, Helga (Geologische Blätter für Nordost-Bayern und angrenzende Gebiete, 2016)
In dieser Arbeit wird im Rahmen des Projekts »Erkundung des geologischen Untergrunds in Nordost-Bayern als Grundlage zur Bewertung des geothermischen Potentials« die Höhenlage der Dogger/Malm-Grenze untersucht. Dazu werden aus bestehenden amtlichen, geologischen Karten (GK), sowie digitalen Geländemodellen (DGMs) Strukturkarten dieser geologischen Grenze erstellt und als 3D-Modell dargestellt. Dafür werden geologische Karten und DGM-Daten ausgewertet, deutlich an der Oberfläche ausstreichende Störungen erfasst und der Verlauf der Grenze anhand der Geländemorphologie in Form von einzelnen Höhenpunkten (HP) eingezeichnet. Dabei ist zu beachten, dass die wahre Grenze oftmals durch Ablagerungen von Massenbewegungen überlagert wird, weshalb diese Ablagerungen zusätzlich erfasst werden müssen. Da die Abrisse meist großen Klüften folgen, können diese auch in die Karte aufgenommen werden. Daraufhin werden Homogenbereiche festgelegt, in denen das Gebiet von Störungen unbeeinflusst ist. Auf diese Weise wurde eine tektonische Übersichtskarte des Untersuchungsgebietes erstellt. Dort können schließlich Höhenpunkte gleicher Höhenlage verbunden und so Strukturlinien eingezeichnet werden. Durch Parallelverschiebung werden aus einer Linie und weiteren Punkten zusätzliche Linien generiert. Unterbrochene oder scharf umbiegende Linien sind Indizien für bislang unbekannte Verwerfungen im Untergrund. Aus den so gewonnenen Daten wird ein 3D-Modell erstellt, das die tektonische Situation im Untersuchungsgebiet wiederspiegelt.
Keywords: 3D-Modellierung; Streichkurven; Dogger/Malm-Grenze

3D morphological analysis of cement over the first 24 hours of hydration by holographic and near-field ptychographic-tomography - Valentini, Luca; Sowoidnich, Thomas; da Silva, Julio Cesar; Schulbert, Christian; Naber, Christoph; Neubauer, Jürgen; Bellmann, Frank (ESRF Coherence Workshop, 2019)

3D MORPHOLOGY OF POST MORTEM ACROTHORACICAN BORINGS IN FAMENNIAN HETEROCORALS – A MORPHOLOGICAL DIVERSIFICATION OR A CONTINUUM ICHNOSPECIES? - Dworczak, Patrycja G.; Jarochowska, Emilia; López Correa, Matthias; Berkowski, Błażej (Annales Societatis Geologorum Poloniae, 2022)
Barnacle borings were found in six heterocoral skeletons. They are present as small (up to 2.9 mm long), slender, pouch-shaped borings with tapering, slit-like openings. The investigated borings were made by acrothoracican cirripedes, which mostly do not have a shell and bore into hard substrates to protect their “naked” bodies. The first occurrence of borings in skeletons of the heterocoral Oligophylloides Różkowska, 1969 from the Upper Devonian Tafilalt Platform was reported recently by Weyer in 2016. Here, the authors present the results of a detailed study of heterocoral remains with numerous acrothoracican borings from Jebel Bou Ifarherioun (Famennian, Anti-Atlas, Morocco). The borings were found on the basal part but also on broken branches and stems of the heterocoral corallum and occurred post mortem. There is no indication of a syn vivo coral-barnacle interaction with borings in tissue-covered areas. The authors used micro-CT scans to visualize the 3D morphology of the pits, their orientation, and distribution. Additionally, the 3D morphology of an assemblage of 75 pits was used to carry out ordination and cluster analyses, which showed that previously proposed ichnospecies may be a continuum of morphological variability. In the basis of measurements by the present authors, the studied borings do not fit any known ichnotaxa. The absence of bourrelets excludes the possibility that the borings studied belong to the ichnogenus Rogerella Saint-Seine, 1951. Hence, the results seem to contradict a synonymization that was proposed by Bromley and D’Alessandro (1987) and subsequent authors and leave room for further research and discussion on this topic. Although the inferred boring organism is a filter feeder and, thus, depends on currents, the authors did not find a preferential orientation of the borings. The samples considered here are the best-preserved Devonian barnacle borings to date.
Created from Fastlane, Scopus look-up
Keywords: Acrothoracican barnacles; bioerosion; Heterocoralia; Late Devonian; Morocco

3. Skultorp Quarry - Ahlberg, Per; Calner, Mikael; Lehnert, Oliver; Lindskog, Anders (The Ordovician of Västergötland and Dalarna, Sweden. Field guide for the ISOS 14 post-conference excursion, 2023)

A 560 yr summer temperature reconstruction for the Western Mediterranean basin based on stable carbon isotopes from Pinus nigra ssp. laricio (Corsica/France). - Szymczak, Sonja; Joachimski, Michael; Bräuning, Achim; Hetzer, Timo; Kuhlemann, Joachim (Climate of the Past, 2012)
The Mediterranean is considered as an area which will be affected strongly by current climate change. However, temperature records for the past centuries which can contribute to a better understanding of future climate changes are still sparse for this region. Carbon isotope chronologies from tree-rings often mirror temperature history but their application as climate proxies is difficult due to the influence of the anthropogenic change in atmospheric CO2 on the carbon isotope fractionation during photosynthetic CO2 uptake. We tested the influence of different correction models accounting for plant response to increased atmospheric CO2 on four annually resolved long-term carbon isotope records (between 400 and 800 yr) derived from Corsican pine trees (Pinus nigra ssp. laricio) growing at ecologically varying mountain sites on the island of Corsica. The different correction factors have only a minor influence on the main climate signals and resulting temperature reconstructions. Carbon isotope series show strong correlations with summer temperature and precipitation. A summer temperature reconstruction (1448–2007 AD) reveals that the Little Ice Age was characterised by low, but not extremely low temperatures on Corsica. Temperatures have been to modern temperatures at around 1500 AD. The reconstruction reveals warm summers during 1480–1520 and 1950–2007 AD and cool summers during 1580–1620 and 1820–1890 AD.
UnivIS-Import:2015-03-09:Pub.2012.nat.dgeo.IGM.LG.a560yr

Abnormal forms of acritarchs (phytoplankton) in the upper Hirnantian (Upper Ordovician) of Anticosti Island, Canada - Delabroye, Aurélien; Munnecke, Axel; Servais, Thomas; Vandenbroucke, Thijs R.A.; Vecoli, Marco (Review of Palaeobotany and Palynology, 2012)
A detailed study of Late Ordovician-early Silurian acritarchs (Palaeozoic phytoplankton) from Anticosti Island (Québec, Canada) revealed an unusually high abundance of abnormal forms from the upper Hirnantian carbonate strata (uppermost Ordovician) of the Ellis Bay Formation in the western part of the island (member 6, . Spinachitina taugourdeaui chitinozoan Biozone). The objective of this paper is to describe these abnormal forms in detail. Two species are particularly affected: . Disparifusa psakadoria Loeblich and Tappan, 1978 presents abnormally hypertrophied central vesicles, whereas . Peteinosphaeridium laframboisepointense nov. sp. has appendices that are fused along their length. The abnormal forms of acritarchs occur in rocks deposited during periods that are near time-equivalents to those of maximum ice-sheet extensions on Gondwana during the Hirnantian glaciation. Although this stratigraphic level corresponds to an interval of strong perturbations of the global carbon cycle, the exact factors causing the observed malformations remain unknown. © 2011
Keywords: Hirnantian; Laurentia; Ordovician-Silurian boundary; Phytoplankton; Teratology

A brief overview of isotope measurements carried out at various CCS pilot sites worldwide - Nowak, Martin; Myrttinen, Anssi; van Geldern, Robert; Becker, Veith; Mayer, Bernhard; Barth, Johannes (Clean Energy Systems in the Underground: Production, Storage and Conversion, 2013)

Abundant taxa determine beta diversity - Roden, Vanessa; Kießling, Wolfgang (Taphos 2017 Vienna - Programme and Abstracts, 2017)

Academic publishing requires linguistically inclusive policies - Arenas-Castro, Henry; Berdejo-Espinola, Violeta; Chowdhury, Shawan; Rodríguez-Contreras, Argelia; James, Aubrie R.M.; Raja, Nussaïbah Begum; Dunne, Emma; Bertolino, Sandro; Emidio, Nayara Braga; Derez, Chantelle M.; Drobniak, Szymon M.; Fulton, Graham R.; et al. (Proceedings of the Royal Society of London, Series B: Biological Sciences, 2024)
Scientific knowledge is produced in multiple languages but is predominantly published in English. This practice creates a language barrier to generate and transfer scientific knowledge between communities with diverse linguistic backgrounds, hindering the ability of scholars and communities to address global challenges and achieve diversity and equity in science, technology, engineering and mathematics (STEM). To overcome those barriers, publishers and journals should provide a fair system that supports non-native English speakers and disseminates knowledge across the globe. We surveyed policies of 736 journals in biological sciences to assess their linguistic inclusivity, identify predictors of inclusivity, and propose actions to overcome language barriers in academic publishing. Our assessment revealed a grim landscape where most journals were making minimal efforts to overcome language barriers. The impact factor of journals was negatively associated with adopting a number of inclusive policies whereas ownership by a scientific society tended to have a positive association. Contrary to our expectations, the proportion of both open access articles and editors based in non-English speaking countries did not have a major positive association with the adoption of linguistically inclusive policies. We proposed a set of actions to overcome language barriers in academic publishing, including the renegotiation of power dynamics between publishers and editorial boards.
CRIS-Team Scopus Importer:2024-03-22
Keywords: academic publishing; biological sciences; inclusivity; language barriers; society journals

A candidate for the Global Stratotype Section and Point at the base of the Serpukhovian in the South Urals, Russia - Richards, B. C.; Nikolaeva, S. V.; Kulagina, E. I.; Alekseev, A. S.; Gorozhanina, E. N.; Gorozhanin, V. M.; Konovalova, V. A.; Goreva, N. V.; Joachimski, Michael; Gatovsky, Y. A. (Stratigraphy and Geological Correlation, 2017)
Keywords: ammonoids; conodonts; foraminifers; GSSP; Lochriea ziegleri; Serpukhovian; South Urals; Viséan

A carbonate carbon isotope record for the late Givetian (Middle Devonian) Global Taghanic Biocrisis in the type region (northern Appalachian Basin) - Zambito, James J.; Joachimski, Michael; Brett, Carlton E.; Baird, Gordon C.; Aboussalam, Z. Sarah (Geological Society of London, 2016)
During the Global Taghanic Biocrisis (c. 385 Ma), Middle Devonian faunas worldwide underwent extinction. In the biocrisis type region, the northern Appalachian Basin, biodiversity changes occurred through three bioevents that ultimately resulted in the loss of numerous endemic taxa. Carbon isotope excursions during this biocrisis have been documented in various stratigraphic successions, but never in the type region. Herein, we reconstruct changes in δC from the biocrisis type region and compare these changes to local faunal transitions. An approximately 1.5‰ negative excursion corresponds to the first bioevent, a time of inferred global warming and replacement of most endemic taxa of the mid-palaeolatitude Appalachian Basin by invasive palaeoequatorial taxa. An approximately 2‰ positive excursion is associated with the second bioevent, recognized as a return of the endemic fauna and the loss of invasive taxa. This positive excursion occurs near the Polygnathus ansatus-Ozarkodina semialternans zonal boundary and is recognized elsewhere. Faunal cosmopolitanism associated with the third bioevent corresponds with an inflection in the carbon isotope record from negative to positive trending values, which agrees with a positive carbon record excursion seen elsewhere at the semialternans-Schmidtognathus hermanni zonal boundary. This new carbon isotope record provides an important reference for recognizing this biocrisis in other areas and facies.

A Case Study of Thermal Evolution in the Vicinity of Geothermal Probes Following a Distributed TRT Method - Schwarz, Hans; Badenes, Borja; Wagner, Jan; Cuevas, Jose Manuel; Urchueguia, Javier; Bertermann, David (Energies, 2021)
To meet the stated climate change targets and to ensure the capability of meeting the current and future energy demands, there is an urgent need to develop renewable energy sources, such as geothermal systems. If geothermal systems are to be cost-efficient and are to enjoy public confidence, it is essential that they are designed and installed in accordance with the prevailing site-specific conditions. A thorough understanding of the thermal behaviour of the surrounding ground is, therefore, critical. In this work, we investigated temperature and its evolution in the vicinity of a shallow geothermal helix-shaped borehole heat exchanger (BHE). To measure the temperature close to the actual geothermal system, an additional U-tube probe was installed at the edge of the same borehole. A thermal load was then applied to the BHE, and the temperature was detected in the nearby U-tube. The temperature measurements were made with a GEOSniff monitoring device. To understand these localised temperature measurements in the context of the Valencia test site, ERT measurements were also performed. The GEOSniff device permits measurements to be made with very high depth resolution, which allows the thermal properties of the surrounding ground to be derived precisely, thus, enabling the identification of the different textural domains.<br
Keywords: thermal evolution; thermal soil properties; shallow geothermal systems; distributed thermal response test (DTRT); wireless distributed temperature sensing (DTS); electrical resistivity tomography (ERT)

A Case Study On Bioerosion In Fossil Cephalopods From The Upper Carboniferous Buckhorn Asphalt Quarry Lagerstätte, Oklahoma, USA - Seuß, Barbara; Nützel, Alexander (GSA, 2018)
Cephalopod remains from the Desmoinesian (Pennsylvanian, Upper Carboniferous) Buckhorn Asphalt Quarry (Oklahoma, USA) were studied intensively over the past decades. However, this is the first study that focusses exclusively on bioerosion affecting their shells. Research on bioerosion in these fossils was possible due to soaking of sediments and shells with hydrocarbons, during or shortly after time of deposition, that sealed open space and prevented strong diagenesis. The shells derive from the ‘cephalopod coquina’ that represents the deepest-water deposit within the single cycle of trans- and regression in the outcrop. The cephalopod remains comprise fragments of both, orthoconic and coiled nautiloid specimens as well as those from ammonoids. The shells were cast and investigated with a scanning electron microscope. The study revealed a diverse association of ichnotaxa and ichnoforms (twenty-two in total, eight of them new – among them six ichnoforms could derive from foraminiferans - and twelve with their oldest record in the Carboniferous) comprising chlorophyte, cyanobacterial, and rhodophyte traces. Fungal and spongial traces as well as those of so far unknown origin are also recorded. Most common are Ichnoreticulina elegans (a chlorophyte trace), a new morphotype of Scolecia isp. (probably produced by cyanobacteria) as well as the fungal (Schizochytrium sp.) trace Flagrichnus profundus, the ‘extremely thin form’ (likely the Conchocelis-stage of Porphyra sp. or Bangia sp.), and the ‘superthin form’ that is produced by some unknown organotroph. Straight nautiloids are intensively bored by I. elegans and Scolecia n. isp. while in the shells of coiled cephalopods F. profundus, the ‘extremely thin form’, and the ‘superthin form’ are most abundant. The ichnotaxon associations in the shells indicate different modes of deposition: Shells of coiled specimens seem to have drifted for a while and were therefore more prone to bioerosion by autotrophs until they sank to the seafloor, while those of the orthocones sank more rapidly with deposition in the deep euphotic to dysphotic zone of the ichnobathymetrical scheme. A comparison with the studies on extant Nautilus supports the idea that ichnotaxa present in Carboniferous cephalopods have gone lost with the extinction of thes

Accelerated increase in plant species richness on mountain summits is linked to warming - Steinbauer, Manuel; Grytnes, John-Arvid; Jurasinski, Gerald; Kulonen, Aino; Lenoir, Jonathan; Pauli, Harald; Rixen, Christian; Winkler, Manuela; Bardy-Durchhalter, Manfred; Barni, Elena; Bjorkman, Anne; Breiner, Frank T.; et al. (Nature, 2018)
Globally accelerating trends in societal development and human environmental impacts since the mid-twentieth century are known as the Great Acceleration and have been discussed as a key indicator of the onset of the Anthropocene epoch. While reports on ecological responses (for example, changes in species range or local extinctions) to the Great Acceleration are multiplying, it is unknown whether such biotic responses are undergoing a similar acceleration over time. This knowledge gap stems from the limited availability of time series data on biodiversity changes across large temporal and geographical extents. Here we use a dataset of repeated plant surveys from 302 mountain summits across Europe, spanning 145 years of observation, to assess the temporal trajectory of mountain biodiversity changes as a globally coherent imprint of the Anthropocene. We find a continent-wide acceleration in the rate of increase in plant species richness, with five times as much species enrichment between 2007 and 2016 as fifty years ago, between 1957 and 1966. This acceleration is strikingly synchronized with accelerated global warming and is not linked to alternative global change drivers. The accelerating increases in species richness on mountain summits across this broad spatial extent demonstrate that acceleration in climate-induced biotic change is occurring even in remote places on Earth, with potentially far-ranging consequences not only for biodiversity, but also for ecosystem functioning and services.<br

Accelerating effect of Li2CO3 on formation of monocarbonate and Al-hydroxide in a CA-cement and calcite mix during early hydration - Manninger, Tanja; Jansen, Daniel; Neubauer, Jürgen; Götz-Neunhoeffer, Friedlinde (Cement and Concrete Research, 2019)
QXRD, calorimetry and pore water analysis were performed, to gain insight into accelerating mechanism of Li2CO3 on CA-cement with CaCO3 (filler and reactant) and investigate its impact on phase formation. Data were combined with thermodynamic modeling (PhreeqC and GEMS) to gain the equilibrium phase assemblage for comparison. Acceleration was reached by adding 0.05 wt% Li2CO3 to a CA-CaCO3 mix. Early increase of pH during hydration and higher pH after the main reaction were observed by adding Li2CO3. Total heat of hydration after 20 h was higher in the sample without Li2CO3. The determined crystalline hydrate content disclosed significant differences. The reference mixture showed 8 wt% CAH10 while there was none in the mixture accelerated by Li2CO3. The detected amount of monocarbonate (CO2-AFm) after 20 h was doubled when accelerated by Li2CO3. Formation of a layered double hydroxide, formula [Al2Li(OH)6]2·X·nH2O (with X = ½·CO3 2− or OH−), acting as catalyst was considered.
CRIS-Team Scopus Importer:2019-11-12

Acceleration of OPC by CAC in binary and ternary systems: The role of pore solution chemistry - Nehring, Jörg; Neubauer, Jürgen; Berger, S.; Götz-Neunhoeffer, Friedlinde (Cement and Concrete Research, 2018)
In dry-mortar-formulations calcium aluminate cement (CAC) is often used as a set accelerator for ordinary Portland cement (OPC). However, a critical amount of CAC is able to delay not only the silicate reaction but also the renewed C3A dissolution of an OPC. This delay can be counteracted by adding an appropriate amount of calcium sulfate (C) to the mix OPC/CAC. The initial hydration period is dominated by fast ettringite formation from CA (CAC) and CaSO4 from OPC generating early strength. High aluminum and low calcium concentrations in the pore solution probably hinder C-S-H seeding and precipitation, thus preventing alite dissolution. Aluminum has to be initially removed by precipitating hydrate phases to change the pore solution chemistry. The start of the silicate reaction is then induced by increasing the calcium concentration in the pore solution.<br
Keywords: Portland cement (D); X-ray diffraction (B); Calcium aluminate cement (D); Monosulfate (D); Kinetics (A)

Accounting for uncertainty from zero inflation and overdispersion in paleoecological studies of predation using a hierarchical Bayesian framework - Smith, Jansen; Handley, John C.; Dietl, Gregory P. (Paleobiology, 2021)
The effects of overdispersion and zero inflation (e.g., poor model fits) can result in misinterpretation in studies using count data. These effects have not been evaluated in paleoecological studies of predation and are further complicated by preservational bias and time averaging. We develop a hierarchical Bayesian framework to account for uncertainty from overdispersion and zero inflation in estimates of specimen and predation trace counts. We demonstrate its application using published data on drilling predators and their prey in time-averaged death assemblages from the Great Barrier Reef, Australia. Our results indicate that estimates of predation frequencies are underestimated when zero inflation is not considered, and this effect is likely compounded by removal of individuals and predation traces via preservational bias. Time averaging likely reduces zero inflation via accumulation of rare taxa and events; however, it increases the uncertainty in comparisons between assemblages by introducing variability in sampling effort. That is, there is an analytical cost with time-averaged count data, manifesting as broader confidence regions. Ecological inferences in paleoecology can be strengthened by accounting for the uncertainty inherent to paleoecological count data and the sampling processes by which they are generated.
CRIS-Team Scopus Importer:2021-09-24

A chaetetid sponge assemblage from the Desmoinesian (Upper Moscovian) Buckhorn Asphalt Quarry lagerstätte in Oklahoma, USA - Seuß, Barbara; Senowbari-Daryan, Baba; Nützel, Alexander; Dittrich, Sebastian; Neubauer, Jürgen; Neubauer, Jürgen (Rivista Italiana Di Paleontologia E Stratigrafia, 2014)
The first detailed study on chaetetids from the Buckhorn Asphalt Quarry Lagerstätte is presented. Among the investigated specimens we found two samples (chaetetid specimens 2 and 6) that are different from all others in the quarry. Thin sections of these display a complex fragmentation of these Buckhorn chaetetids. Additionally, one of these samples contains two chaetetid morphotypes growing side by side, thus, in the same paleoenvironment. These specimens differ in their mode of growth (laminar and domical), which suggests that chaetetid growth was most likely influenced by genetic factors rather than by the paleoenvironment. We observed a feature, not hitherto reported as far as we are aware, on the surface of chaetetids; namely a regular clustering of seven tubules surrounding a central tubule. This feature could have had an exhalant function. Mineralogical analyses of the skeleton indicate primary high magnesian-calcite mineralogy, which is in accordance with reports in the literature. Cements precipitated during diagenesis are either calcite or dolomite and, where associated with microbial mats, they may contain a distinct amount of manganese. The comparison of the chaetetid skeletons from the Buckhorn Asphalt Quarry leads to the impression, that they represent various morphotypes or even species. Because of the lack of unique features, we have refrained however, from describing new species.
UnivIS-Import:2015-04-14:Pub.2014.nat.dgeo.IGM.LP.achaet
Keywords: Buckhorn asphalt quarry; Chaetetida; Hypercalcified sponges; Pennsylvanian; Taphonomy

Acid rain footprint three decades after peak deposition: Long-term recovery from pollutant sulphate in the Uhlirska catchment (Czech Republic) - Marx, Anne; Hintze, Simone; Sanda, Martin; Jankovec, Jakub; Oulehle, Filip; Dusek, Jaromir; Vitvar, Tomas; Vogel, Tomas; van Geldern, Robert; Barth, Johannes (Science of the Total Environment, 2017)
Keywords: Catchment; Export; Groundwater; Mass balance; Soil water; Sulphur

A close look at Late Carboniferous Algal Mounds: Schulterkofel, Carnic Alps, Austria. - Joachimski, Michael; et al. (Facies, 2003)
During the uppermost Carboniferous and lowermost Permian algal mounds were formed in inner shelf settings of the Carnic Alps (Austria/Italy). A specific mound type, characterized by the dominance of the dasyclad green alga Anthracoporella was studied in detail with regard to geometry, relationship between mound and intermound rocks, composition of the sediment, biota and diagenetic criteria. The two meter-sized mounds studied, occur within depositional sequences of transgressive systems tracts in the Lower Pseudoschwagerina Limestones (uppermost Gzhelian) at the flank of the Schulterkofel. The mounds consist of an Anthracoporella core facies with a sponge-crust boundstone facies at the base and at the top. The massive limestones of the Anthracoporella core facies exhibit abundant algal tufts and bushes, frequently in life position. The limestones of the intermound facies represented by thin-bedded bioclastic wackestones and packstones with abundant phylloid algae underlie and overlie the mounds. Intercalations of intermound beds within the mound facies indicate sporadic disruption of mound growth. Onlapping of intermound beds on steep mound flanks indicate rapid stabilization and lithification of mound flanks and the existence of a positive paleorelief. Asymmetrical shape of the mounds may be current controlled. Mound and intermound biota differ in the prevailing algae but are relatively similar with regard to associated foraminifera. Conspicuous differences concern bioerosion and biogenic encrustations. Both are high in intermound areas but low in the Anthracoporella core facies. The mounds show no ecological zonation. The mounds grew by in-place accumulation of disintegrated algal material and trapped bioclastic material between erect algal thalli. The comparison of the various Anthracoporella mounds demonstrates that almost each mound had ist own history. Establishing a general model for these mounds is a hazardous venture.
Keywords: Algae (Anthracoporella); Algal reefs; Carnic Alps (Austria); Facies analysis; Late Carboniferous; Reef mounds; Smaller foraminifera

A cold supergene zinc deposit in Alaska: The Reef Ridge case - Santoro, L.; Boni, M.; Mondillo, N.; Joachimski, Michael; Woodman, J. (Geological Society of America Bulletin, 2015)
The Reef Ridge deposit is a typical supergene "nonsulfide" zinc mineralization, located in the Yukon-Koyukuk region of west-central Alaska (USA). It is hosted in sedimentary rocks of the Farewell terrane, a continental fragment sandwiched between the Siberian and Laurentian cratons during the early Paleozoic. The mineralization occurs in Lower-Middle Devonian shallowwater dolomite of a Paleozoic carbonate platform succession belonging to the Nixon Fork tectonic unit. The mineralization consists of oxidized minerals associated with minor remaining sulfides (pyrite/marcasite and sphalerite). In the oxidation zone, smithsonite is the predominant mineral, mixed with Fe- (hydr)oxides (goethite and hematite). A complete petrographic and mineralogical study was performed. Samples were analyzed by X-ray diffraction, inductively coupled plasma-mass spectrometry and emission spectrometry, energy dispersive scanning electron microscopy, and QEMSCAN®( quantitative evaluation of minerals by scanning electron microscopy). The most abundant mineral in the nonsulfide ore is smithsonite. Similar to other nonsulfide Zn deposits worldwide, the first generation of smithsonite has replaced both primary sphalerite and the host carbonates. A second smithsonite generation precipitated as cement in vugs, cavities, and fractures. Minorzinc amounts also occur in the Fe-(hydr) oxides, and zinc traces have been identified in clay minerals. The carbon and oxygen isotope values of smithsonite at Reef Ridge vary from -0.7 to 2.1% relative to Vienna Peedee belemnite (VPDB) and 19.1% to 21.9% relative to Viennastandard mean ocean water (VSMOW). The δC values are similar to those of the host rock, suggesting that the predominant carbon source for smithsonite was the host carbonates, with only a limited contribution from organic carbon. The oxygen isotope ratios of Reef Ridge smithsonite are more depleted in O compared to supergene nonsulfides from other parts of the world formed under warm-humid, temperate, or semiarid climates. The oxygen isotope fractionation between water and smithsonite, which relates the δO value of the mineralizing solution, the formation temperature of smithsonite, and its δO composition, indicates that the δO composition of Reef Ridge smithsonite is related to very low formation temperatures ( 10 °C), and strong depletion in O of the precipitating waters. The δO smithsonite composition, the strong O depletion, and the relationship of the formation of the Reef Ridge nonsulfide deposit with the development of the Sleetmute upland surface (which started in the Late Tertiary and continues to the present) indicate that the formation of the Reef Ridge nonsulfide deposit is probably related to cold/humid weathering episodes during a period comprised between Late Tertiary and Holocene. The "traditional" interpretation on the genesis of Zn nonsulfide deposits in warmhumid, temperate, or semiarid conditions should be questioned where other climate zones are indicated.

A common high-pressure metamorphic evolution of interlayered eclogites and metasediments from the ‘ultrahigh-pressure unit’ of the Tianshan metamorphic belt in China - Li, Jilei; Klemd, Reiner; Gao, Jun; Jiang, Tuo; Song, Yun-Hui (Lithos, 2015)
Petrological and mineralogical data of interlayered eclogite, marble and quartz–mica schist from a drill core are used to constrain the metamorphic evolution of metavolcanics and intercalated metasediments in the Tianshan (ultra-)high-pressure/low-temperature [(U)HP/LT] metamorphic belt, NW China. The eclogite mainly consists of varying amounts of garnet, omphacite, quartz and zoisite, the marble of calcite (> 95 vol.%) with minor zoisite and phengite, and the schist of quartz and mica with minor calcite, chlorite, albite and garnet. Using garnet isopleth thermobarometry, pseudosection calculations for the eclogite and quartz–mica schist reveal a common metamorphic evolution under HP condition of both rock types that is also consistent with the temperature estimates for the marble using conventional thermometry. The uniform P–T paths of the interlayered eclogite and quartz–mica schist, as well as compatible temperature data of the marble, document that the whole rock suite constitutes a coherent HP unit during peak metamorphic conditions and exhumation. Thus protoliths of eclogite and associated sediments are believed to have undergone the same metamorphic evolution. In addition, the data gained by the present study of the HP rocks, which were collected in the northern part of the Chinese Tianshan (U)HP/LT belt, do not support the recently proposed tectonic scheme that this metamorphic terrane consists of a northern “coherent UHP unit” and a southern “coherent HP unit”.<br
Keywords: High pressure; Eclogite; Pseudosection; P–T evolution; Tianshan

A comparative structural study of wet and dried ettringite - Renaudin, G.; Filinchuk, Y.; Neubauer, Jürgen; Götz-Neunhoeffer, Friedlinde (Cement and Concrete Research, 2010)
Two different techniques were used to compare structural characteristics of "wet" ettringite (stored in the synthesis mother liquid) and "dried" ettringite (dried to 35% relative humidity over saturated CaCl2 solution). Lattice parameters and the water content in the channel region of the structure (site occupancy factor of the water molecule not bonded to cations) as well as microstructure parameters (size and strain) were determined from a Rietveld refinement on synchrotron powder diffraction data. Local environment of sulphate anions and of the hydrogen bonding network was characterized by Raman spectroscopy. Both techniques led to the same conclusion: the "wet" ettringite sample immersed in the mother solution from the synthesis presents similar structural features as ettringite dried to 35% relative humidity. An increase of the a lattice parameter combined with a decrease of the c lattice parameter occurs on drying. The amount of structural water, the point symmetry of sulphate and the hydrogen bond network are unchanged when passing from the wet to the dried ettringite powder. Ettringite does not form a high-hydrate polymorph in equilibrium with alkaline solution, in contrast to the AFm phases that lose water molecules on drying. According to these results we conclude that ettringite precipitated in aqueous solution at the early hydration stages is of the same chemical composition as ettringite present in the hardening concrete. © 2009 Elsevier Ltd. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2010.nat.dgeo.IGM.LM.acompa
Keywords: Crystal structure (B); Ettringite (D); Hydration (A); Raman spectroscopy (B); X-ray diffraction (B)

A comparative study of the effects of two alkanolamines on cement hydration - Lu, Zichen; Kong, Xiangming; Jansen, Daniel; Zhang, Chaoyang (Advances in Cement Research, 2021)
The effects of two alkanolamines, triethanolamine (TEA) and diethanol-isopropanolamine (DEIPA), on cement hydration were comparatively investigated by several techniques including calorimetry, in situ X-ray diffraction analysis and pore solution analysis. Results show that the cement hydration regime is greatly altered by the alkanolamines, depending on their types and dosages. At the dosage of 0.5%, the aluminate reactions, including the formation of AFt and the reaction of C4AF, are greatly accelerated, and consequently the silicate hydration is retarded. Compared to DEIPA, TEA increases the [Al] in pore solution, probably due to the stronger complexation with aluminate ions (Al(OH)4-), while DEIPA notably enhances the dissolution of C4AF after depletion of gypsum, suggesting a stronger complexation with iron ions (Fe3+). Through a comparison of the hydration of pure alite and cement systems, it is found that the effects of the two alkanolamines on cement hydration are primarily influenced by their impacts on the aluminate reaction.
CRIS-Team Scopus Importer:2021-11-26
Keywords: admixtures; aluminates; calorimetry

A comparison of the magmatic evolution of pacific intraplate volcanoes: Constraints on melting in mantle plumes - Haase, Karsten; Beier, Christoph; Kemner, Fabian (Frontiers in Earth Science, 2019)
The interaction of deep mantle plumes with lithospheric plates is one fundamental concept of plate tectonics. Based on observations mainly made on the Hawaiian volcanoes the compositional evolution of hotspot volcanoes is believed to reflect the variation of partial melting and source composition as the plate moves across the different melting zones of the mantle plume. The model predicts the formation of several magmatic stages that differ in composition. In order to test this model, we compare published compositional and age data from the intraplate volcanoes of the Hawaii, Society, Marquesas and Samoa hotspots on the older part of the Pacific Plate. The compiled data indicate that most volcanoes display variations within and between several magmatic series, and in most cases the more evolved lavas are associated with the voluminous shield stage. The Hawaiian volcanoes show up to four different series ranging from tholeiites to nephelinites/melilitites, whereas the other hotspots mainly erupt two magmatic series consisting of transitional basalts and basanites. Submarine preshield stages at the Society and Marquesas hotspots resemble those observed at Hawaii. The large variation of primitive magmas in the Hawaiian plume as opposed to the other Pacific intraplate systems may reflect the higher temperatures, higher buoyancy flux, and extreme chemical heterogeneity at Hawaii. The shield stage activity at all four hotspots lasts for 1 million years indicating similar widths of the melting zone, although the temperatures of the distinct mantle plumes vary considerably. The relatively depleted shield stage magmatism typically overlaps by ∼200 kyrs with the formation of the more enriched postshield magmas indicating that the two melting and magma ascent systems exist contemporaneously.
CRIS-Team Scopus Importer:2019-06-18
Keywords: Geochemistry; Hawaii; Hotspots; Mantle melting; Marquesas; Samoa; Society

A Conceptual Framework for Measuring Ecological Novelty - Staples, Timothy L.; Blois, Jessica; Cramer, Katie L.; Cunningham, Emer T.; Dornelas, Maria; Haberle, Simon G.; Heger, Tina; Kießling, Wolfgang; Magurran, Anne E.; O'Dea, Aaron; Penny, Amelia M.; Radeloff, Volker C.; et al. (Global Ecology and Biogeography, 2025)
Background: Human pressures are driving the emergence of unprecedented, ‘novel’, ecological and environmental systems. The concept of novel (eco)systems is well accepted by the scientific community, but the use and measurement of novelty has outgrown initial definitions and critiques. There are still unresolved methodological and conceptual differences in quantifying novelty that prevent a unified research approach. Framework: Here we present a conceptual framework and guidelines to unify past and future measurement of ecological novelty. Under this framework, novelty is a property of an ecological or environmental entity of interest. Novelty is quantified as the comparison between the target entity and a reference set, measured as the summary of degrees of difference across one or more dimensions. Choices in these components, particularly the reference set, can change resulting novelty measurements and inferences. Showcase: We provide a case-study to showcase our framework, measuring pre- and post-European novelty in 99 pollen assemblages in Midwest USA forests. We paired this quantitative exploration with a five-step process designed to improve the utility and outcomes of novelty analyses. Conclusions: Quantitative novelty has immense value in studies of abrupt ecological change, linking climatic and ecological change, biotic interactions and invasions, species range shifts and fundamental theories. Our framework offers a unified overview and is also primed for integration into management and restoration workflows, providing consistent and robust measurements of novelty to support decision making, priority setting and resource allocation.
CRIS-Team Scopus Importer:2025-03-14
Keywords: anomaly detection; community composition; dissimilarity; multidimensional comparisons; no analog communities; novel communities; novel ecosystems

A continental comparison indicates long-term effects of forest management on understory diversity in coniferous forests - Schmiedinger, Andreas; Kreyling, Jürgen; Steinbauer, Manuel; Macdonald, Ellen; Jentsch, Anke; Beierkuhnlein, Carl (Canadian Journal of Forest Research-Revue Canadienne De Recherche Forestiere, 2012)
Promotion of species diversity has become a major goal in forestry. This requires an understanding of the impacts of management disturbance on species diversity relative to natural drivers such as climatic or edaphic conditions on the relevant temporal scales, i.e., centuries. We examined the effects of long-term management disturbance on understory plant diversity in coniferous forests by comparing structure types (ages since disturbance) between regions with comparable abiotic settings but contrasting management history, i.e., management for centuries in central Europe versus the first logging in primary forests in western Canada. We systematically sampled three age classes after disturbance and compared their alpha diversity and species composition. The structure types (age classes) showed similar differences in alpha diversity in both landscapes, while the response of species compositions differed between the two. Fewer late-successional specialists occurred in the European landscape. Within the setting of our study, the structure types, which reflect the time since major forest management disturbance, affected understory species richness and composition at least as strongly as environmental conditions such as climate, soil, and tree layer diversity across the broad altitudinal gradients that we sampled. Our results suggest that forest management affects the diversity of coniferous forests, with management for centuries disadvantaging late-successional specialists. Furthermore, it appears that human action is becoming the major determinant of diversity of coniferous forests, emphasizing the need for sustainable management schemes.

A contribution to the characterization of the silicate-water interface – Part II: Atom Probe Tomography of tricalcium silicate - Naber, Christoph; Sowoidnich, T.; Bellmann, F.; Neubauer, Jürgen; DeRocher, K. A.; Joester, D. (Micron, 2018)
Keywords: Atom probe tomography; Ca3SiO5; Calcium-Silicate-Hydrate (C-S-H); Focused ion beam

A contribution to the characterization of the silicate-water interface – Part I: Implication of a new polished sample hydration technique - Sowoidnich, T.; Gordon, L.; Naber, Christoph; Bellmann, F.; Neubauer, Jürgen; Joester, D. (Micron, 2018)
Keywords: Atom probe tomography; Cement; Hydration; Tricalcium Silicate

Acritarch distribution along an inshore-offshore transect in the Gorstian (lower Ludlow) of Gotland, Sweden - Stricanne, Ludovic; Munnecke, Axel; Pross, Jörg; Servais, Thomas; Munnecke, Axel; Munnecke, Axel (Review of Palaeobotany and Palynology, 2004)
To better understand palaeoecological signatures in Palaeozoic acritarch assemblages, the distribution of palynomorphs has been quantitatively studied in eight localities from the Gorstian, lower Ludlow (Late Silurian) of Gotland, Sweden. The localities are situated along an inshore-offshore transect comprising shallow marine lagoonal environments to distal shelf facies. Process-bearing acritarchs and sphaeromorphs constitute the main components within the palynomorph assemblages. The lateral distribution of palynomorphs exhibits characteristic features at three different levels as follows. (1) With regard to the overall composition of the palynomorph assemblages, the abundance of process-bearing acritarchs increases towards the distal shelf, while the abundance of sphaeromorphs decreases. (2) At the generic level, the acritarchs Micrhystridium and Dilatisphaera are more abundant in the proximal facies, while Evittia, Percultisphaera and Oppilatala are more common in distal environments. (3) At an infrageneric level, Micrhystridium morphotypes with shorter processes are mainly present in proximal environments, while those with longer and ramified processes occur in more distal shelf environments. The palynomorph distribution along the inshore-offshore transect highlights the potential of acritarchs and prasinophytes as palaeoenvironmental indicators. © 2004 Elsevier B.V. All rights reserved.
Keywords: acritarchs; Gotland; Ludlow; palaeoecology; palynomorphs; Silurian

Acritarch distribution in the Middle Ordovician of Öland, Sweden: Ecostratigraphical or biostratigraphical signal? - Calero Gordon, Jaqueline L.; Chaigneau, Baptiste; Lindskog, Anders; Eriksson, Mats E.; Manzano, Eiver G.; Monnet, Claude; Munnecke, Axel; Régnier, Sylvie; Servais, Thomas (Palaeogeography, Palaeoclimatology, Palaeoecology, 2025)
The Middle Ordovician of the palaeocontinent Baltica provides some of the best preserved and most diverse acritarch assemblages of the lower Palaeozoic. A great number of widely used acritarch genera and species have been described from this area since the 1960s and many of these taxa are considered as biostratigraphically useful for both regional and international correlation. Here, we document the changing proportion of acritarch morphotypes through two well-documented Darriwilian (Middle Ordovician) sections of Öland, Sweden. Progressive changes of key morphological characters, such as the standard process length, as well as the relative abundance of different morphotypes, are continuous throughout the sections. These changes in the acritarch assemblages parallel the transition from deeper to shallower water environments as deduced from local facies analyses and regional sedimentation patterns. Consequently, the previously suggested biostratigraphical signals in the acritarch assemblages could also be interpreted as ecophenotypical responses to the changing palaeoenvironment. Therefore, the morphological plasticity of acritarchs challenges their accuracy and validity for precise correlation if their palaeoecology is not addressed.
CRIS-Team Scopus Importer:2025-05-23
Keywords: Acritarchs; Biostratigraphy; Correlation; Ordovician; Palaeoecology; Phytoplankton

Adaptive Behavior of Dynamic Orthoester Cryptands - Shyshov, Oleksandr; Brachvogel, Rene-Chris; Bachmann, Tobias; Srikantharajah, Rubitha; Segets, Doris; Hampel, Frank; Puchta, Ralph; Von Delius, Max (Angewandte Chemie International Edition, 2017)
The integration of dynamic covalent bonds into macrocycles has been a tremendously successful strategy for investigating noncovalent interactions and identifying effective host–guest pairs. While numerous studies have focused on the dynamic responses of macrocycles and larger cages to various guests, the corresponding constitutionally dynamic chemistry of cryptands remains unexplored. Reported here is that cryptands based on orthoester bridgeheads offer an elegant entry to experiments in which a metal ion selects its preferred host from a dynamic mixture of competing subcomponents. In such dynamic mixtures, the alkali metal ions Li+, Na+, K+, Rb+, and Cs+ exhibit pronounced preferences for the formation of cryptands of certain sizes and donor numbers, and the selection is rationalized by DFT calculations. Reported is also the first self-assembly of a chiral orthoester cryptate and a preliminary study on the use of stereoisomers as subcomponents.
Keywords: cryptands; dynamic combinatorial chemistry; supramolecular chemistry; host–guest chemistry; NMR spectroscopy

Adding fossil occupancy trajectories to the assessment of modern extinction risk - Kießling, Wolfgang; Kocsis, Ádám (Biological Letters, 2016)
Besides helping to identify species traits that are commonly linked to extinction risk, the fossil record may also be directly relevant for assessing the extinction risk of extant species. Standing geographical distribution or occupancy is a strong predictor of both recent and past extinction risk, but the role of changes in occupancy is less widely assessed. Here we demonstrate, based on the Cenozoic fossil record of marine species, that both occupancy and its temporal trajectory are significant determinants of risk. Based on extinct species we develop a model on the additive and interacting effects of occupancy and its temporal changes on extinction risk. We use this model to predict extinction risk of extant species. The predictions suggest a moderate risk for marine species on average. However, some species seem to be on a long-term decline and potentially at a latent extinction risk, which is not considered in current risk assessments.

Adding Some Samples - Munnecke, Axel (Microfacies of Carbonate Rocks - Analysis, Interpretation and Application, 2009)
Due to the work by Erik Flügel, who passed away far too early in 2004, microfacies investigations of carbonate rocks have a long tradition in our institute in Erlangen (Germany). He stimulated several generations of geologists in the field of carbonate sedimentology, and it is a great honor for me to provide a small additional chapter to the present book. The chapter presents examples from a variety of depositional environments and ages. The thin sections have been prepared for the international microfacies courses held in Erlangen regularly since 1974. The chapter has two goals. On one side, thin sections have been chosen which complement the previous chapters, and provide some additional information, on the other, this chapter is intended as some sort of self-test. Before reading the figure captions you might try to study the pictures and build your own interpretation
Keywords: microfacies; carbonate rocks; samples; interpretation; thin sections

Addressing priority questions of conservation science with palaeontological data - Kießling, Wolfgang; Raja, Nussaïbah Begum; Roden, Vanessa; Turvey, Samuel T.; Saupe, Erin E. (Philosophical Transactions of the Royal Society B-Biological Sciences, 2019)

A Decision Support System (DSS) and a design tool for helping stakeholders and designers in the choice of GSHPs - de Carli, Michele; Castelruiz Aguirre, Amaia; Zarrella, Angelo; Cardoso, Lucia; Noyé, Sarah; Gast, Robert; Graci, Samantha; Emmi, Giuseppe; Bertermann, David; Müller, Johannes; Galgaro, Antonio; Dalla Santa, Giorgia; et al. (European Geothermal Congress, 2019)

A delayed end-Permian extinction in deep-water locations and its relationship to temperature trends (Bianyang, Guizhou Province, South China) - Jiang, Haishui; Joachimski, Michael; Wignall, Paul B.; Zhang, Muhui; Lai, Xulong (Palaeogeography, Palaeoclimatology, Palaeoecology, 2015)
Keywords: Bianyang; Conodont; End-Permian extinction; South China

A derived sauropodiform dinosaur and other sauropodomorph material from the Late Triassic of Canton Schaffhausen, Switzerland - Rauhut, Oliver W.M.; Holwerda, Femke Marleen; Furrer, Heinz (Swiss Journal of Geosciences, 2020)
Although sauropodomorph dinosaurs have been known for a long time from the Late Triassic of central Europe, sauropodomorph diversity and faunal composition has remained controversial until today. Here we review sauropodomorph material from the Canton Schaffhausen, Switzerland. The material comes from three different but geographically close localities and represents at least three different taxa. Apart from the common genus Plateosaurus, the material includes remains of two different large, robustly built sauropodomorphs. One of these is described as a new taxon, Schleitheimia schutzi n. gen. et sp., on the basis of an unusual ilium and associated axial and appendicular material. Schleitheimia represents a derived basal sauropodiform and possibly the immediate outgroup to Sauropoda, and thus is the most derived sauropodomorph known from the Late Triassic of Europe. These results thus highlight the diversity of sauropodomorphs in the Late Triassic of central Europe and further indicate widespread sauropodomorph survival across the Triassic-Jurassic boundary.
CRIS-Team Scopus Importer:2020-07-10
Keywords: Late Triassic; Sauropod origins; Sauropodomorpha; Switzerland

A discussion and proposal concerning the use of the term calcispheres - Versteegh, Gerard J.M.; Servais, Thomas; Munnecke, Axel; Streng, Michael; Vachard, Daniel (Palaeontology, 2009)
The terminology and grouping of spherical, calcareous microfossils of unknown biological affinity, usually referred to as calcispheres, are diffuse. The term calcispheres is inconsistently used, the morphological and taxonomical concepts are mostly ill-defined and a formal definition is lacking. To resolve this issue, we propose, in analogy with the erection of the Acritarcha for organic microfossils of unknown origin, a new group called Calcitarcha, including all calcareous microfossils with a central cavity for which the biological affinities remain unknown. © The Palaeontological Association, 2009.
Keywords: calcareous microfossil; calcisphere; Calcitarcha; Nomenclature; pithonelloid; gilianelloid

Advanced Monitoring of H2S Injection through the Coupling of Reactive Transport Models and Geophysical Responses - Ciraula, Daniel A.; Kleine-Marshall, Barbara; Galeczka, Iwona M.; Lévy, Léa (Environmental Science & Technology, 2024)
Hydrogen sulfide (H2S), an environmentally harmful pollutant, is a byproduct of geothermal energy production. To reduce the H2S emissions, H2S-charged water is injected into the basaltic subsurface, where it mineralizes to iron sulfides. Here, we couple geophysical induced polarization (IP) measurements in H2S injection wells and geochemical reactive transport models (RTM) to monitor the H2S storage efforts in the subsurface of Nesjavellir, one of Iceland’s most productive geothermal fields. An increase in the IP response after 40 days of injection indicates iron-sulfide formation near the injection well. Likewise, the RTM shows that iron sulfides readily form at circumneutral to alkaline pH conditions, and the iron supply from basalt dissolution limits its formation. Agreement in the trends of the magnitude and distribution of iron-sulfide formation between IP and RTM suggests that coupling the methods can improve the monitoring of H2S mineralization by providing insight into the parameters influencing iron-sulfide formation. In particular, accurate fluid flow parameters in RTMs are critical to validate the predictions of the spatial distribution of subsurface iron-sulfide formation over time obtained through IP observations. This work establishes a foundation for expanding H2S sequestration monitoring efforts and a framework for coupling geophysical and geochemical site evaluations in environmental studies.
CRIS-Team Scopus Importer:2024-06-21
Keywords: basalt; geothermal wastewater; hydrogen sulfide; induced polarization; mineral storage; pyrite; wireline logging

Advanced Rietveld refinement and SEM analysis of tobermorite in chemically diverse autoclaved aerated concrete - Schreiner, Jürgen; Götz-Neunhoeffer, Friedlinde; Neubauer, Jürgen; Bergold, Sebastian; Webler, Ralf; Volkmann, Stephan; Jansen, Daniel (Powder Diffraction, 2019)
Changes of structural properties of tobermorite in autoclaved aerated concrete (AAC) for various compositions were characterized and the disadvantages of SEM analysis in this context are discussed. The influence of variations in the chemical composition of raw materials on lattice parameters, morphology and domain sizes of tobermorite was investigated by XRD and for comparison by SEM analysis. Particularly the effect of substitution by Al3+ and (SO4)2− in tobermorite structure was examined. The dimensions of coherently scattering domains were calculated based on the refinement of anisotropic peak broadening of tobermorite in XRD diffractograms using a Rietveld compatible approach. No effect of (SO4)2− on the domain sizes and lattice parameters of tobermorite could be observed. The amount of anhydrite detected by quantitative XRD analysis indicates that all of the available (SO4)2− is present as anhydrite. Lath-like shapes of domains and a larger c parameter are calculated whenever Al3+ is incorporated in a considerable amount. Formation of katoite can be observed very clearly in SEMmicrographs whenever the amount of available Al3+ exceeds a distinct value in the dry mix. The effect of Al3+ and (SO4)2− on tobermorite morphology could not be observed clearly by SEM analysis in AAC samples.<br

Advanced Rietveld refinement and SEM analysis of tobermorite in chemically diverse autoclaved aerated concrete - Götz-Neunhoeffer, Friedlinde; Schreiner, Jürgen; Neubauer, Jürgen; Jansen, Daniel; Bergold, Sebastian; et al. (Powder Diffraction, 2019)

Advancements in enforced C2S wet carbonation: Leveraging δ13C isotope tracking for reaction insights - Singer, Marie; van Geldern, Robert; Barth, Johannes; Jansen, Daniel (Journal of CO2 Utilization, 2024)
This study concerns wet carbonation of β-C2S (Ca2SiO4) in a closed system at 23 °C. The progress of carbonation was detected by quantitative X-ray diffraction (QXRD) and thermogravimetric analysis (TGA). Further measurements of pH and ion concentrations as well as modelling carbon species and saturation indices were done. Additionally, stable carbon isotope ratios (δ13C) in CO2, dissolved inorganic carbon (DIC) and carbonate phases were measured. The aim of this study was to investigate δ13C isotope values during C2S carbonation. If a systematic fractionation of carbon isotopes occurs during the reaction, it can help to quantify the carbonation reaction. During the carbonation process over 48 h, we found carbon isotope distributions from the gaseous phase to the solution and ultimately to the solid phase. Calculations confirm the direct relation of δ13C values to the carbonation progress. With this, stable isotope measurements offer a promising tool to monitor the reaction progress in-situ.
CRIS-Team Scopus Importer:2024-09-20
Keywords: Carbonation; clinker phases; CO; isotope fractionation; stable carbon isotopes

Advances in Stable Isotope Monitoring of CO2 Under Elevated Pressures, Temperatures and Salinities: Selected Results from the Project CO2ISOLABEL - Barth, Johannes; Mader, Michael; Myrttinen, Anssi; Becker, Veith; van Geldern, Robert; Mayer, Bernhard (Geological Storage of CO2 – Long Term Security Aspects, 2015)

A first find of retrogressed eclogites in the Odenwald Crystalline Complex, Mid-German Crystalline Rise, Germany: evidence for a so far unrecognised high-pressure metamorphism in the Central Variscides - Will, Thomas M.; Schmädicke, Esther (Lithos, 2001)
UnivIS-Import:2017-03-24:Pub.2001.nat.dgeo.IGM.profes_1.afirst

A first glimpse on the taphonomy and sedimentary environment of the Eocene siliceous sponges from Chiampo, Lessini Mts, NE Italy - Frisone, Viviana; Preto, Nereo; Pisera, Andrzej; Agnini, Claudia; Giusberti, Luca; Papazzoni, Cesare Andrea; De Angeli, Antonio; Beschin, Claudio; Mietto, Paolo; Quaggiotto, Ermanno; Monaco, Paolo; Dominici, Stefano; et al. (Bollettino Della Societa Paleontologica Italiana, 2020)
A diverse assemblage of bodily preserved sponges has been recovered from a lower Lutetian tuffite horizon in the Chiampo Valley, Lessini Mountains, Italy. The sponge assemblage is dominated by hexactinellids and lithistids. Using uniformitarian criteria, the composition of the assemblage suggests a water depth greater than 200 m. Sponges are often preserved in growth position including sponge clusters. Taphonomic processes facilitating sponge preservation include rapid burial of a living sponge community and early diagenetic calcification. Different modes of attachment suggest heterogeneous substrate conditions. The associated fauna, such as abundant pteropods in the matrix and in-situ preserved crinoids, confirms a rather deep-water environment. However, there are also common benthic elements of shallow-water origin. Although some of these elements show signs of transport, others, such as decapod crustaceans, do not. Moreover, trace fossils indicate high-energy environments. To reconcile these observations, we propose rapid, tectonically triggered sea-level changes.
CRIS-Team WoS Importer:2021-01-29

A first Palaeozoic-type echinoderm group representative from the Mesozoic - Reich, Mike; Stegemann, Tanja R.; Hausmann, Imelda M.; Roden, Vanessa; Nützel, Alexander (GeoBonn 2018, Living Earth - Abstracts, 2018)

A first report of the Ludlow Lau Event from the Prague Basin (Barrandian, Czech Republic) - Buggisch, Werner; Fryda, Jiri; Lehnert, Oliver; Manda, Štěpán (Serie Correlación Geológica, 2003)
UnivIS-Import:2015-03-09:Pub.2003.nat.dgeo.IGM.LG.afirst

Age constraints on high-pressure/low-temperature metamorphism and sedimentation in the Luk Ulo Complex (Java, Indonesia) - Hoffmann, J.; Broecker, M.; Setiawan, N.; Klemd, Reiner; Berndt, J.; Maulana, A.; Baier, H. (Lithos, 2019)
Pre-Cenozoic blueschist- and eclogite-facies rocks occur widely scattered in the central Indonesian region, possibly representing lateral equivalents of the same subduction zone. High-pressure/low-temperature (HP/LT) metamorphism is thought to have occurred during the Early Cretaceous, which however is only constrained by K–Ar ages. This study is part of a systematic re-investigation of the regional geochronological record of various metamorphic rocks from this belt and focuses on the Luk Ulo Complex in central Java. Rubidium–Sr multipoint isochrons of one eclogite, two epidote-glaucophane schistsand one epidote amphibolite yielded Early Cretaceous (Aptian) ages of 119–117 Ma (± 0.6–0.8 Ma). These ages are similar to previously reported K–Ar results, indicating that the existing data had not significantly been compromised by extraneous Ar contamination. Relatively low peak metamorphic temperatures (ca. 400 °C) during the HP/LT stage suggest that the Rb–Sr isotopic system was not significantly affected by diffusive loss during cooling. The Rb–Sr ages most likely constrain the time of mica growth or recrystallization during high-pressure metamorphism. The matching ages of high-pressure and lower pressure rocks are attributed to inheritance, but mixing of rocks that originally had formed at the same time at different depths of the subduction complex cannot completely be ruled out yet. Rubidium–Sr white mica ages of eclogite- and blueschist-facies rocks from central Java are younger than those of similar rocks from the Western Sulawesi tectonic province (130–120 Ma), revealing a previously unknown age difference that had been hidden by the poorer precision of the K–Ar dataset. At this point, it remains unclear whether this age difference is related to processes operating within the same or in different subduction zones. The zircon populations of clastic metasedimentary rocks from the Luk Ulo Complex are dominated by a prominent Jurassic to Carboniferouspopulation (ca. 320–180 Ma) with a distinct Permo-Triassic peak (ca. 270–200 Ma). Another less pronounced Paleozoic age signal shows up at 450–380 Ma. Proterozoic and Archean zircon grains are very rare. At least some data points at the lower end of the age spectrum (ca.135–117 Ma) most likely are related to in-situ metamorphic processes. The youngest zircon grains of unambiguous detrital origin show up at ca. 160 Ma, indicating a Late Jurassic maximum depositional age. Additional detrital zircon data for the Barru Complex (Western Sulawesi) further substantiate previous findings documenting a complex age spectrum with contributions of Mesozoic (Triassic), Paleozoic (Permian, Carboniferous, Devonian to Ordovician), Meso- to Paleoproterozoic subpopulations and rare Archean zircons. The youngest zircons indicate a maximum depositional age of ca. 255–250 Ma. New and existing U–Pb zircon data indicate that the pre-metamorphic basin histories recorded in the Luk Ulo and Barru complexes are linked to different source terrains and depositional system
CRIS-Team WoS Importer:2019-02-21
Keywords: High-pressure metamorphism; Geochronology; Rb–Sr; U–Pb; Detrital zircon; Luk Ulo complex; Indonesia

Age-depth model for uppermost Ndutu Beds constrains Middle Stone Age technology and climate-induced paleoenvironmental changes at Olduvai Gorge (Tanzania) - Smedley, Rachel K.; Fenn, Kaja; Stanistreet, Ian G.; Stollhofen, Harald; Njau, Jackson K.; Schick, Kathy; Toth, Nicholas (Journal of Human Evolution, 2024)
Olduvai Gorge in northern Tanzania is part of a globally important archeological and paleoanthropological World Heritage Site location critical to our understanding of modern human evolution. The Ndutu Beds in the upper part of the geological sequence at Olduvai Gorge represent the oldest unit to yield modern Homo sapiens skeletal material and Middle Stone Age technology. However, the timing of the deposition of the Ndutu Beds is poorly constrained at present, which limits our understanding of the paleoenvironments critical for contextualizing H. sapiens and related technologies in the Olduvai Basin. Using a suite of 15 luminescence ages of sedimentary core samples, combined with Bayesian statistics, this study provides a new higher-resolution age-depth model for the deposition of the uppermost Upper Ndutu and Naisiuiu Beds cored by the Olduvai Gorge Coring Project. The luminescence and modeled ages are presented as ±1 σ uncertainties. The Ndutu Beds intersected by the Olduvai Gorge Coring Project cores are dated to between 117.1 ± 17.9 and 45.3 ± 4.2 ka (between 125.9 ± 26.5 and 45.8 ± 8.2 ka modeled ages), while a probable overlying layer of Naisiusiu Beds dates to 23.7 ± 10.9 to 12.1 ± 1.7 ka (25.7 ± 18.9 ka and 12.0 ± 3.4 ka modeled age). Time-averaged accretion rates are derived during this time: (1) initially low rates (<5 cm ka-1) from the bottom of the core at 117.1 ± 17.9 ka up to 95.3 ± 11.1 ka (125.9 ± 26.5 to 95.5 ± 23.3 ka modeled ages); (2) the middle section spanning between 95.3 ± 11.1 and 62.7 ± 5.7 ka (95.5 ± 23.3 to 61.9 ± 10.4 ka modeled ages) with mean rates above 15 cm ka-1; and (3) the last 62.7 ± 5.7 ka (61.9 ± 10.4 ka modeled age) where the accretion rate reduces to below 5 cm ka-1. This reduction can be explained by the evolution of the gorge system that was likely driven by subsidence of the Olbalbal depression and changes in climate, particularly precipitation and resulting lake and base level changes. Older Upper Ndutu and Lower Ndutu Beds are contained within proto-gorges within the modern gorge system.
CRIS-Team Scopus Importer:2024-01-12
Keywords: Africa; Archeology; Human evolution; Landscape evolution; Luminescence dating; Stratigraphy

Age determination of nephrite by in-situ SIMS U-Pb dating syngenetic titanite: A case study of the nephrite deposit from Luanchuan, Henan, China - Ling, Xiao-Xiao; Schmädicke, Esther; Li, Qiu-Li; Gose, Jürgen; Wu, Rui-Hua; Wang, Shi-Qi; Liu, Yu; Tang, Guo-Qiang; Li, Xian-Hua (Lithos, 2015)
Keywords: Titanite; Tremolite; Nephrite; SIMS U-Pb dating; Geochronology

Age, geochemistry, and significance of Devonian felsic magmatism in the North Slope subterrane, Yukon, Canadian Arctic - Ward, William P.; Strauss, Justin V.; Johnson, Benjamin G.; Mcclelland, William C.; Colpron, Maurice; von Gosen, Werner; Piepjohn, Karsten; Coble, Matthew A.; Crockford, Peter W.; Landis, Joshua (Circum-Arctic Structural Events: Tectonic Evolution of the Arctic Margins and Trans-Arctic Links with Adjacent Orogens, 2019)
New zircon U-Pb dates from the Mount Fitton, Mount Sedgwick, Mount Schaeffer, Old Crow, and Dave Lord plutons indicate that granitoids of the Old Crow plutonic suite in northern Yukon were emplaced in the North Slope subterrane of the Arctic Alaska composite terrane between 375 +/- 2 Ma and 368 +/- 3 Ma. Whole-rock major and trace element and Nd-Sr isotope geochemistry, combined with zircon trace element and Hf isotope geochemistry, indicate magma genesis involved significant contribution from older continental crust. Samples from the five plutons yield wholerock epsilon Nd-(t) values from -3.9 to -11.6 and Sr-87/Sr-86 (i) ratios of 0.7085-0.7444 and 0.8055. Zircon epsilon Hf-(t) values range from -6.2 to -13.3. These North Slope subterrane granitoids are generally younger and isotopically more evolved than felsic rocks in the Coldfoot and Hammond subterranes of the southern Brooks Range (Arctic Alaska terrane), but in part are coeval with felsic rocks on the Seward and Chukotka peninsulas. The North Slope granitoids are also coeval and geochemically similar to arc magmatism in the Yukon-Tanana terrane in Yukon and on Axel Heiberg and northern Ellesmere islands, Nunavut. The Old Crow plutonic suite is interpreted as part of a Late Devonian arc system developed along the Arctic and Cordilleran margins. Late Devonian plutons were most likely emplaced after initial translation of the North Slope subterrane along the northern Laurentian margin. The plutons lie within or north of the Porcupine shear zone and thus do not limit post-Late Devonian displacement on the boundary between the North Slope subterrane and northwestern Laurentia.
CRIS-Team WoS Importer:2019-11-15

A generalization of the taxon cycle - Steinbauer, Manuel (Journal of Biogeography, 2017)

A generalized geometric approach to anisotropic peak broadening due to domain morphology - Ectors, Dominique; Götz-Neunhoeffer, Friedlinde; Neubauer, Jürgen (Journal of Applied Crystallography, 2015)
This article reports the derivation of a physically based geometric description of the mean diameter of orthogonal shapes and provides an efficient formalism to relate these to reciprocal lattices and corresponding apparent crystallite sizes. The following descriptions provide a reasonable approximation for the simulation and refinement of anisotropic domain morphology in powder diffraction techniques.
Keywords: anisotropic domain morphology; anisotropic peak broadening; Powder diffraction; Rietveld refinement

A geochemical study of off-axis seamount lavas at the Valu Fa Ridge: constraints on magma genesis and slab contributions in the southern Tonga subduction zone. - Haase, Karsten; Fretzdorff, Susanne; Mühe, Richard; Garbe-Schönberg, Dieter; Stoffers, Peter (Lithos, 2009)
New geochemical data are presented for fresh lavas from off-axis seamounts east and west of the Valu Fa Ridge and from seamounts south of the propagating rift tip of the Valu Fa Ridge. Most seamount lavas are basaltic and thus more primitive than the mostly andesitic to dacitic lavas from the adjacent Valu Fa Ridge. Slight differences in fluid-mobile element ratios and in Sr isotope ratios suggest small-scale heterogeneities of the slab component in this region with an apparently higher sedimentary input into the off-axis seamount lavas than into the island arc magmas. Off-axis volcanoes near back-arc basin spreading centres thus resemble off-axis seamounts adjacent to mid-oceanic ridges which also show more extreme compositions than the well-homogenized mid-ocean ridge basalts. The geochemical variations support a diapiric ascent of the hydrated or partially molten mantle leading to separate magma supply systems for the different volcanic structures. The mantle wedge between the Valu Fa Ridge and the island arc appears to be uniformly depleted in fluid-immobile incompatible elements compared to average depleted mid-ocean ridge basalts whereas lavas from seamounts west of the Valu Fa Ridge show less depletion in agreement with a depletion event of the whole mantle wedge in the backarc melting zone. Seamount lavas south of the Valu Fa Ridge propagating rift resemble the Valu Fa lavas indicating an increased magma production caused by the influx of water into the mantle. © 2009 Elsevier B.V. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2009.nat.dgeo.IGM.legeo.ageoch
Keywords: Basalts; Hydrous fluid; Sr-Nd-Pb isotopes; Trace elements; Volcanism

A geographic database approach to the KT boundary - Kießling, Wolfgang; Claeys, Philippe (Geological and biological effects of impact events, 2001)
UnivIS-Import:2015-04-20:Pub.2001.nat.dgeo.IGM.LP.ageogr

Aggradation and carbonate accumulation of Holocene Norwegian cold-water coral reefs - Titschack, Jürgen; Baum, Daniel; De Pol-Holz, Daniel; López Correa, Matthias; Forster, Nina; Flögel, Sascha; Hebbeln, Dierk; Freiwald, André (Sedimentology, 2015)
Cold-water coral ecosystems present common carbonate factories along the Atlantic continental margins, where they can form large reef structures. There is increasing knowledge on their ecology, molecular genetics, environmental controls and threats available. However, information on their carbonate production and accumulation is still very limited, even though this information is essential for their evaluation as carbonate sinks. The aim of this study is to provide high-resolution reef aggradation and carbonate accumulation rates for Norwegian cold-water coral reefs from various settings (sunds, inner shelf and shelf margin). Furthermore, it introduces a new approach for the evaluation of the cold-water coral preservation within coldwater coral deposits by computed tomography analysis. This approach allows the differentiation of various kinds of cold-water coral deposits by their macrofossil clast size and orientation signature. The obtained results suggest that preservation of cold-water coral frameworks in living position is favoured by high reef aggradation rates, while preservation of coral rubble prevails by moderate aggradation rates. A high degree of macrofossil fragmentation indicates condensed intervals or unconformities. The observed aggradation rates with up to 1500 cm kyr-1 exhibit the highest rates from cold-water coral reefs so far. Reef aggradation within the studied cores was restricted to the Early and Late Holocene. Available datings of Norwegian cold-water corals support this age pattern for other fjords while, on the shelf, cold-water coral ages are reported additionally from the early Middle Holocene. The obtained mean carbonate accumulation rates of up to 103 g cm-2 kyr-1 exceed previous estimates of cold-water coral reefs by a factor of two to three and by almost one order of magnitude to adjacent sedimentary environments (shelf, slope and deep sea). Only fjord basins locally exhibit carbonate accumulation rates in the range of the cold-water coral reefs. Furthermore, cold-water coral reef carbonate accumulation rates are in the range of tropical reef carbonate accumulation rates. These results clearly suggest the importance of cold-water coral reefs as local, maybe regional to global, carbonate sinks.
UnivIS-Import:2016-06-01:Pub.2015.nat.dgeo.IGM.LP.aggrad
Keywords: Aggradation rate; Carbonate accumulation rate; Cold-water coral carbonate factory; Cold-water coral reef; Holocene reef development

A giant boring in a Silurian stromatoporoid analysed by computer tomography - Beuck, Lydia; Wisshak, Max; Munnecke, Axel; Freiwald, André (Acta Palaeontologica Polonica, 2008)
This study describes the largest known Palaeozoic boring trace, Osprioneides kampto igen. et isp. nov., found within a stromatoporoid Densastroma pexisum from the Upper Visby Formation (lower Wenlock, Silurian) on the island of Gotland, Sweden. Differences between the physical properties of the stromatoporoid, and the dense micritic infilling of the borings allowed the application of the CT-scan technology for the 2D and 3D-visualisation of this rare trace. The additional application of a stereoscopic technique on these CT images and movies enhances its value for unravelling spatial orientations. This non-destructive method has a great potential for future macro- as well as microboring analyses, The trace maker, most likely a worm, infested the hosting colony post-mortem with up to 120 mm long borings measuring 5-17 mm in diameter. Smaller forms of Trypanites and Palaeosabella within the same stromatoporoid preferentially occur in the outer coenosteum and occasionally in abandoned borings of O. kampto. The stratigraphic position of O. kampto follows the "Great Ordovician Biodiversification Event" in time, and reflects the increase in diversity of boring species. Borings with penetration-depths of 120 mm are, however, unique findings for the Palaeozoic and were not exceeded until some 260 million years later (Bajocian, Middle Jurassic) when the "Mesozoic Marine Revolution" led to convergent reinventions as a result of enhance predation, grazing pressure, and ecospace competition.
Keywords: Bioerosion; trace fossil; Osprioneides; stromatoporoid; computed tomography; Silurian; Gotland

A GIS-based study of earthquake hazard as a tool for the microzonation of Bucharest - Rohn, Joachim; et al. (Engineering Geology, 2006)
Bucharest, the capital of Romania, is situated close to one of the most seismically active areas in Europe: the Vrancea region in the Eastern Carpathians. The necessity of a well-documented microzonation of the city and its immediate surroundings is clearly evident due to this seismic risk. In the absence of a sufficient dense network of ground motion recording stations in Bucharest, the only possible way to realise a comprehensive microzonation is to correlate detailed, subsurface geological data at instrumented sites with the macroseismic intensities and to extrapolate the results to non-instrumented areas. In this regards, the geology of Bucharest is relatively well known, based on a great number of geotechnical drillings (about 1200). For the first time, a digital geological model (DGM) of the subsurface of Bucharest was obtained based on the integration of numerous borehole data with a geographic information system (GIS). Transfer functions and dynamic ground responses were calculated with the linear modelling software ProShake® using soil profiles taken from discrete locations in the developed model and shear wave velocities and densities, characteristic for each Quaternary unit. The distribution of computed spectral amplifications and spectral accelerations were generated for the ground surface of Bucharest by interpolation. Important insights were made concerning the primary geological influencing factors on the observed historical damages to buildings, which resulted from earthquakes, through statistical regression analyses between various geotechnical properties and parameters associated with the historical damages. © 2006.
UnivIS-Import:2015-03-09:Pub.2006.nat.dgeo.IGM.profes_3.agisba
Keywords: Geographic information system (GIS); Geotechnical parameters; Microzonation; Site amplification

A high-resolution carbon balance in a small temperate catchment: insights from the Schwabach River, Germany - Lee, Kern; van Geldern, Robert; Barth, Johannes (Applied Geochemistry, 2017)

A Hirnantian (latest Ordovician) reefal bryozoan fauna from Anticosti Island, eastern Canada: Taxonomy and chemostratigraphy - Ernst, Andrej; Munnecke, Axel (Canadian Journal of Earth Sciences, 2009)
The Natiscotec outcrop on Anticosti Island, Canada (Ellis Bay Formation, Laframboise Member, Hirnantian, Late Ordovician), exposes a patch reef some 20-30 m in diameter, 2-3 m thick, with abundant rugose corals, as well as favositids and heliolitids. Reef capping and flanking sediments include typical Hirnantian brachiopods, such as Hirnantia, Hindella, and Eospirigerina. Within the reef peloidal microbialites encrusting bryozoan colonies are common. The bryozoan fauna includes three cystoporates, seven trepostomes, and three phylloporines. Two genera and two species are new: the cystoporate Natiscotecella tenuis n. gen. and n. sp. and the phylloporine Dilaminocladia natiscotecensis n. gen. and n. sp. Three more species are also new: the cystoporates Ceramopora clara n. sp. and Acanthoceramoporella spinigera n. sp. and the trepostome Revalotrypa honguedensis n. sp. Furthermore, we identify the three trepostomes Atactoporella aff. ortoni (Nicholson, 1874), Hallopora elegantula (Hall, 1852), and Monotrypella cf. aequalis Ulrich, 1882, and a phylloporine Parachasmatopora porkunensis Lavrentjeva, 1985. Four species are identified at generic level and in open nomenclature: the three trepostomes Lioclemella sp., Calloporella sp., and Trepostomata sp. and a phylloporine ? Ralfinella sp. The bryozoan fauna shows some affinities with the Late Ordovician fauna of Scandinavia. Stable carbon isotope investigations from brachiopod shells of the same outcrop yield values for d13C of up to +6.7%, which represent the highest values reported from the Anticosti succession so far. This indicates that the stratigraphic position of the outcrop is at or close to the peak of the globally recognized Hirnantian δC excursion.
Keywords: Hirnantian; Ordovician; Anticosti Island; Bryozoan Fauna; Taxonomy; Chemostratigraphy

A Late Barrêmian and Early Aptian Vertebrate Fauna of Garbsen near Hanover, Lower Saxony - Biermann, Stefanie; Roden, Vanessa; Karl, Hans-Volker; Reich, Mike (Terra Nostra 2009/3, 2009)

A Late Devonian actinopterygian suggests high lineage survivorship across the end-Devonian mass extinction - Giles, Sam; Feilich, Kara; Warnock, Rachel; Pierce, Stephanie E.; Friedman, Matt (Nature Ecology & Evolution, 2022)
An actinopterygian fossil with unexpected anatomical features from 7 million years before the end-Devonian mass extinction suggests complex patterns of divergence and diversification around the Devonian/Carboniferous boundary for ray-finned fishes.
CRIS-Team WoS Importer:2022-12-02

A Late Ordovician planktic assemblage with exceptionally preserved soft-bodied problematica from the Martinsburg Formation, Pennsylvania - Meyer, Mike B; Ganis, G. Robert; Wittmer, Jacalyn M.; Zalasiewicz, Jan A.; de Baets, Kenneth (Palaios, 2018)
Here we report a locality containing exceptionally preserved (soft-bodied) fossils of mid-Late Ordovician age from the geologically complex Martinsburg Formation in central Pennsylvania. The fossils, which resemble specimens from Burgess Shale-type deposits, include enigmatic specimens (problematica) and phyllocarid arthropods (with preserved appendages) which are associated with graptolites. The locality is notable for preservation of a low diversity community of soft-bodied planktic animals, likely captured and rapidly buried by a turbidity current. The problematica lack sufficient anatomical detail for confident systematic placement; however, they can be superficially compared to a number of possible metazoans including: nominally/non- shelled mollusks (including veligers), cnidarians, lophophorates, or possibly aberrant tube-dwelling priapulids or polychaetes. Overall, the problematica may belong to one (or several) extinct clades or some unknown clade of animal life. The complex geologic history of the region has reduced the resolution of the problematica’s original exceptional preservation, yet the fossils retain many key features. Hence, this locality has implications for our understanding of exceptional preservation, its alteration over geological history, and the planktic communities of ‘‘The Great Ordovician Biodiversification Event’’ (GOBE) in the planktic real

Algae, calcitarchs and the Late Ordovician Baltic limestone facies of the Baltic Basin - Kröger, Björn; Penny, Amelia; Shen, Yuefeng; Munnecke, Axel (Facies, 2020)
The Late Ordovician succession of the Baltic Basin contains a characteristic fine-grained limestone, which is rich in calcareous green algae. This limestone occurs in surface outcrops and drill-cores in an extensive belt reaching from Sweden across the Baltic Sea to the Baltic countries. This limestone, which is known in the literature under several different lithological names, is described and interpreted, and the term “Baltic limestone facies” is suggested. The microfacies, from selected outcrops from the Åland Islands, Finland and Estonia, consists of calcareous green algae as the main skeletal component in a bioclastic mudstone-packstone lithology with a pure micritic matrix. Three types of calcitarch, which range in diameter from c. 100–180 μm, are common. Basinward, the youngest sections of the facies belt contain coral-stromatoporoid patch reefs and Palaeoporella-algal mounds. The Baltic limestone facies can be interpreted as representing the shallow part of an open-marine low-latitude carbonate platform.
CRIS-Team Scopus Importer:2019-11-26
Keywords: Calcitarch; Dasycladacales; Lithographic limestone; Ordovician; Shallow-water carbonates

Alinite-cement made from waste incineration residues - from basic research to applications - Motzet, Hubert; Neubauer, Jürgen; Pöllmann, Herbert (16th International Conference on Cement Microscopy, 1994)
UnivIS-Import:2015-04-16:Pub.1994.nat.dgeo.IGM.LM.alinit_0

Alinite - Chemical composition, solid solution and hydration behavior - Neubauer, Jürgen; Pöllmann, Herbert (Cement and Concrete Research, 1994)
The chemical composition of alinite was investigated in the system CaO SiO2Al2O3MgOCaCl2. Solid solution was observed. The formula should be written as Ca10Mg1-x/2□x/2[(SiO4)3+x(AlO4)1-x/O2Cl] with 0.35<x<0.45 .="" a="" alinites="" behaviour.="" calorimetric="" chemical="" composition="" difference="" different="" free="" hydration="" in="" inf="" investigations="" lattice="" means="" no="" of="" show="" significant="" synthesized="" their="" with="">2 (chloride not combined with alinite) which is present after synthesis influences the hydration. Calorimetric and SEM investigations lead to the following equation: alinite + H2O → C3A·CaY2·10H2O + Ca(OH)2 + CSH(Cl?)-gel ⇒ Y = Cl-, OH-, 1 2 CO3 2-. © 1994.</x<0.45>
UnivIS-Import:2015-03-05:Pub.1994.nat.dgeo.IGM.LM.alinit

Alite dissolution and C-S-H precipitation rates during hydration - Naber, Christoph; Bellmann, F.; Sowoidnich, T.; Götz-Neunhoeffer, Friedlinde; Neubauer, Jürgen (Cement and Concrete Research, 2019)
An extensive dataset suitable for kinetic calculations was collected for the hydration of monoclinic alite at water to solid ratios of 10 and 0.5. The measurement methods used to investigate the hydration behavior are XRD, TGA, solid state NMR, BET, SEM and ICP-OES. A comparison of the two water to solid ratios shows only minor effects of the w/s-ratio on the reaction kinetics. Reaction rates for the two kinetic steps alite dissolution and C-S-H precipitation are calculated from this dataset and compared to the measured reaction rates. Computed reaction rates from C-S-H precipitation show a good match with the measured reaction rates, indicating that the computation incorporates all relevant factors related to C-S-H precipitation kinetics during hydration.<br
Keywords: Pore solution (B); Hydration (A); Kinetics (A); Calcium-Silicate-Hydrate (C-S-H) (B); Ca3SiO5 (D)

Alkenones in Pleistocene Upper Bed I (1.803–1.900 Ma) sediments from Paleolake Olduvai, Tanzania - Brassell, Simon C.; Colcord, Devon E.; Shilling, Andrea M.; Stanistreet, Ian G.; Stollhofen, Harald; Toth, Nicholas; Schick, Kathy D.; Njau, Jackson K.; Freeman, Katherine H. (Organic Geochemistry, 2022)
The Olduvai Gorge Coring Project (OGCP) recovered sequences of Pleistocene lake sediments that correlate with those known from outcrops directly associated with hominin fossil horizons. The sedimentary succession from Core 2A (02◦ 58′ 43′’ S, 035◦ 19′ 25.5′’ E), which targeted the ancient lake-basinal depocenter, includes stratigraphic intervals ( 1.86 Ma) sandwiched between the Bed I basalt and Tuff IF dated horizons, where remains of two hominin holotypes have been recovered. The lower part of this sequence (72.3–86.9 mbs) consists of lacustrine claystones interbedded with sandy claystones characterized by high Corg (av. 2.5%) and includes several laminated intervals. It displays shifts in terrestrial vegetation recorded by values for δ13CTOC and δ2HnC31 that reflect changes in the proportions of C3 vs C4 plants and precipitation, respectively. These temporal profiles represent higher-resolution signatures of the precession-scale wet/dry cycles previously recognized in the outcropping sedimentary succession of Olduvai Gorge. Several samples from this interval contain alkenones comprising C37 and C39 alkadien-2-ones and alkatrien-2-ones, and C38 and C40 alkadien-3-ones and alkatrien-3-ones. They are distinguished from the vast majority of alkenone distributions reported in lake sediments from polar and temperate latitudes (e.g., Greenland, N. and S. America, Europe, Russia, China, S. Africa, Antarctica) by the absence of tetraunsaturated alkenones (e.g., C37:4). The alkenone distributions vary stratigraphically with higher concentrations in the drier intervals of the precession-scale cycles that exhibit characteristics resembling those of Group II haptophytes found in contemporary saline/alkaline environments rather than those of Group I haptophytes from freshwater ecosystems. Paleolake Olduvai represents the first reported occurrence of alkenones in a low-latitude Pleistocene lake, where the absence of alkatetraenones may reflect contributions from strains of Group II haptophytes that are favored by warmer temperatures or saline conditions. Temporal variations in unsaturation indices (UK’ 37, UK’ 38) and the proportions of alken-2-ones and alken-3-ones likely reflect influences on alkenone production by haptophytes that are associated with changes in the lake environment primarily driven by hydrologic cycles (e.g., salinity and alkalinity) rather than lake temperatures.<br
Keywords: Hominin evolution; Lacustrine sediments; Alkenones; Biomarkers

Allogenic succession in Late Ordovician reefs from southeast China: a response to the Cathaysian orogeny - Li, Qijian; Li, Yue; Kießling, Wolfgang (Estonian Journal of Earth Sciences, 2015)
Several Late Ordovician (late Katian) reef complexes are known from the border area of Jiangxi and Zhejiang provinces in southeast China. We studied two coral-stromatoporoid reefs exposed in the Xiazhen Formation at Zhuzhai (Yushan, Jiangxi). The reefs have a combined thickness of 7.4 m and are metazoan-dominated with most reef-builders in growth position. Stromatoporoids and tabulate corals constitute the framework of the reefs. Stromatoporoids (mostly Clathrodictyon) dominate the first unit and show a vertical increase in proportion and dominance from the middle part to the top of the unit, whereas tabulate corals (dominated by Catenipora and Agetolites) are the main reef-builders in the second unit where stromatoporoids are rare. We attribute this change to a greater tolerance of tabulate corals to turbidity, allowing them to thrive in the muddy facies of the upper unit. This facies change is probably related to the increasing terrestrial input from the northwestward expansion of the Cathaysian Land during the late Katian. The Cathaysian orogeny also led to a short-term exposure of the sea floor in the study area, which terminated the reef growth.
UnivIS-Import:2015-07-08:Pub.2015.nat.dgeo.IGM.LP.alloge
Keywords: Allogenic succession; Cathaysian orogeny; Coral-stromatoporoid reefs; Late Katian; Xiazhen Formation

Al-Mg and U-Pb chronological records of Erg Chech 002 ungrouped achondrite meteorite - Reger, Philip M.; Roebbert, Yvonne; Neumann, Wladimir; Gannoun, Abdelmouhcine; Regelous, Marcel; Schwarz, Winfried H.; Ludwig, Thomas; Trieloff, Mario; Weyer, Stefan; Bouvier, Audrey (Geochimica Et Cosmochimica Acta, 2023)
Achondrite meteorites are remnants of the earliest planetary differentiation processes in the Solar System. They have been used to anchor short-lived radiochronometers to absolute ages determined from long-lived radiochronometers. More specifically, when comparing the isotopic systematics of the short-lived 26Al-26Mg chronometer anchored to absolute U-corrected Pb-Pb ages, inferences about the distribution of 26Al (half-life of ∼717 000 yr) in the protoplanetary disk can be evaluated. The ungrouped achondrite Erg Chech (EC) 002 has a distinct mineralogy and more evolved elemental composition compared to basaltic achondrites. In situ and solution 26Al-26Mg chronometry and 53Mn-53Cr chronometry suggest that EC 002 formed within ∼0.7 to 2.2 Ma after the formation of Ca-Al-rich inclusions (CAIs), making it the oldest known sample of igneous crust in the Solar System (Barrat et al., 2021; Anand et al., 2022; Zhu et al., 2022; Fang et al., 2022). Here we present the U-corrected Pb-Pb age and 26Al-26Mg age obtained by MC-ICPMS solution analysis of the same mineral separate samples of EC 002. In addition, six merrillite grains were analyzed by in-situ SIMS to determine their Pb-Pb individual ages. The U isotope composition of EC 002 exhibits internal heterogeneities between leached pyroxene (238U/235U = 137.766 ± 0.027) and the bulk rock (238U/235U = 137.8190 ± 0.0074). The Pb isotope composition of progressively leached pyroxenes are characterized by radiogenic 206Pb/204Pb ratios (ranging from 41 to 23487). Using the U isotope composition of the leached pyroxenes, the resulting age of the 207Pb/206Pb-204Pb/206Pb isochron is 4565.87 ± 0.30 Ma (2σ). The weighted mean of the Pb-Pb ages of seven SIMS analyses of merrillites are 4564.3 ± 5.2 Ma (2σ). These similar ages (within uncertainty) indicate rapid cooling and the absence of significant thermal events after ∼4559 Ma on the parent body of EC 002. The 26Al-26Mg isochron through a bulk rock, pyroxene, fine-grained and four plagioclase fractions defines an initial 26Al/27Al ratio of [8.89 ± 0.79] × 10−6 corresponding to a formation age of 1.83 ± 0.12 Ma after CAIs ([5.23 ± 0.13] × 10−5; Jacobsen et al., 2008). The initial 26Al abundance is consistent with previous MC-ICP-MS 26Al-26Mg reported systematics for EC 002 (Fang et al., 2022), but 0.46 ± 0.13 Myr older than the in situ SIMS 26Al-26Mg age previously reported by Barrat et al. (2021).When anchored to the absolute Pb-Pb age of CV3 CAIs (4567.30 ± 0.16 Ma; Connelly et al., 2012), the Al-Mg model age of EC 002 is 4565.47 ± 0.20 Ma, slightly younger than its U-corrected Pb-Pb age. The concordance of the Pb-Pb and 26Al-26Mg ages of ungrouped CC achondrites when anchored to EC 002 suggest that 26Al was homogeneously distributed between the NC and CC reservoirs at the time of their parent body accretion. Furthermore, the presence of internal U isotope heterogeneities found between mineral and whole-rock samples of EC 002 supports the need of U isotope analysis of meteoritic samples dated using the Pb-Pb chronometer.
CRIS-Team Scopus Importer:2023-02-17
Keywords: Achondrite; Al-Mg chronology; Early Solar System; Planetary differentiation; U-Pb chronology

Almost 200 billion litres later - Barth, Johannes; Liedl, Rudi (Grundwasser, 2013)

Altered volcanic ashes in Palaeocene and Eocene sediments of the Eureka Sound Group (Ellesmere Island, Nunavut, Arctic Canada) - Reinhardt, Lutz; Estrada, Solveig; Andruleit, Harald; Dohrmann, Reiner; Piepjohn, Karsten; von Gosen, Werner; Davis, Donald W.; Davis, Bill (Zeitschrift der Deutschen Gesellschaft für Geowissenschaften, 2013)
Keywords: Smectite-bentonite; Crandallite; Bentonite geochronology; Mount Lawson Formation; Margaret Formation

Altitude isotope effects in Mediterranean high-relief terrains: a correction method to utilize stream water data - Hemmerle, H.; van Geldern, Robert; Juhlke, Tobias; Huneau, F.; Garel, E.; Santoni, S.; Barth, Johannes (Hydrological Sciences Journal-Journal Des Sciences Hydrologiques, 2021)
Quantification of the isotope altitude effect from precipitation allows the identification of recharge altitudes in high-relief areas. However, steep terrains frequently limit the use of this precipitation-based approach. Perennial rivers often provide easy, year-round access for water sampling. However, in high-relief regions rivers may not adequately represent regional precipitation isotope patterns because they integrate isotope signals along their course. This prevents the calculation of an altitudinal isotope gradient from river water samples alone. We present a study that shows how a river-based sampling approach served to determine the altitude effect. Replacing the original sample site altitude with the mean upstream catchment elevation as calculated from a digital elevation model allowed us to establish a plausible altitude isotope effect from stream water. The correction approach was verified independently using precipitation isotope data. This approach can potentially be transferred to other regions where precipitation sampling at various elevations is difficult to determine.
CRIS-Team WoS Importer:2021-07-16

Aluminat- und Ferrat-Phasen - Struktur-Kristallchemie-Eigenschaft komplexer Oxidverbindungen - Göbbels, Matthias (European Journal of Mineralogy, 1997)
UnivIS-Import:2015-03-05:Pub.1997.nat.dgeo.IGM.LM.alumin

A Maastrichtian microbial reef and associated limestones in the Roca Formation of Patagonia - Kießling, Wolfgang; Scasso, Roberto A.; Aberhan, Martin; Ruiz, Lucas; Weidemeyer, Sven (Fossil Record, 2006)
We describe a small microbial reef and associated limestones occurring in a Maastrichtian transgressive succession of mixed carbonate-siliciclastic lithologies at Sierra Huantraico near Chos Malal (Neuquén, Argentina). Strontium isotope data suggest that the reef is of earliest Maastrichtian age. The small reef (0.8 m thick, 2 m wide) is mostly composed of peloidal bindstone, dense stromatolite-cement crusts and thrombolite. Except for some ostracods, no metazoan fossils were found in the reef structure, although the majority of peloids are fecal pellets, probably of larger crustaceans. Small foraminifers with calcite tests and probable green algae have also been noted. Sedimentological data and fossils within and immediately above the reef suggest that the reef was formed in a transgressive systems tract under freshwater to brackish-water conditions. Limestones above the reef are serpulid-bryozoan packstones and intraclast-ooid grainstones. These limestones yield a mixture of typical non-tropical (common serpulids and bryozoans) and typical tropical aspects (common dasycladaceans and ooids). This mosaic is explained by salinity fluctuations, which in our case dominate over temperature in determining the grain associations. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
UnivIS-Import:2015-03-09:Pub.2006.nat.dgeo.IGM.LP.amaast
Keywords: Carbonate sedimentology; reef biology

A macroevolutionary analysis of European Late Upper Palaeolithic stone tool shape using a Bayesian phylodynamic framework - Matzig, David N.; Marwick, Ben; Riede, Felix; Warnock, Rachel (Royal Society Open Science, 2024)
Phylogenetic models are commonly used in palaeobiology to study the patterns and processes of organismal evolution. In the human sciences, phylogenetic methods have been deployed for reconstructing ancestor–descendant relationships using linguistic and material culture data. Within evolutionary archaeology specifically, phylogenetic analyses based on maximum parsimony and discrete traits dominate, which sets limitations for the downstream role cultural phylogenies, once derived, can play in more elaborate analytical pipelines. Recent methodological advances in Bayesian phylogenetics, however, now allow us to infer evolutionary dynamics using continuous characters. Capitalizing on these developments, we here present an exploratory analysis of cultural macroevolution of projectile point shape evolution in the European Final Palaeolithic and earliest Mesolithic (approx. 15 000–11 000 BP) using a Bayesian phylodynamic approach and the fossilized birth–death process model. This model-based approach leaps far beyond the application of parsimony, in that it not only produces a tree, but also divergence times, and diversification rates while incorporating uncertainties. This allows us to compare rates to the pronounced climatic changes that occurred during our time frame. While common in cultural evolutionary analyses of language, the extension of Bayesian phylodynamic models to archaeology arguably represents a major methodological breakthrough.
CRIS-Team Scopus Importer:2024-09-06
Keywords: archaeology; Bayesian phylogenetics; cultural macroevolution; geometric morphometrics; Late Upper Palaeolithic; stone tools

A major anomaly in the carbon cycle during the late Cisuralian (Permian): Timing, underlying triggers and implications - Liu, Chao; Du, Yuansheng; Jarochowska, Emilia; Yan, Jiaxin; Munnecke, Axel; Lu, Gang (Palaeogeography, Palaeoclimatology, Palaeoecology, 2018)
Keywords: Kungurian; Mass-balance calculation; Methane; Negative excursion; Organic carbon isotopes

A major perturbation of the global carbon budget in the Early-Middle Frasnian transition (Late Devonian). - Racki, Grzegorz; Joachimski, Michael; Morrow, Jared R. (Palaeogeography, Palaeoclimatology, Palaeoecology, 2008)
UnivIS-Import:2015-03-09:Pub.2008.nat.dgeo.IGM.LG.amajor

A metasomatized lithospheric mantle control on the metallogenic signature of post-subduction magmatism - Holwell, David A.; Fiorentini, Marco; McDonald, Iain; Lu, Yongjun; Giuliani, Andrea; Smith, Daniel J.; Keith, Manuel; Locmelis, Marek (Nature Communications, 2019)
Ore deposits are loci on Earth where energy and mass flux are greatly enhanced and focussed, acting as magnifying lenses into metal transport, fractionation and concentration mechanisms through the lithosphere. Here we show that the metallogenic architecture of the lithosphere is illuminated by the geochemical signatures of metasomatised mantle rocks and post-subduction magmatic-hydrothermal mineral systems. Our data reveal that anomalously gold and tellurium rich magmatic sulfides in mantle-derived magmas emplaced in the lower crust share a common metallogenic signature with upper crustal porphyry-epithermal ore systems. We propose that a trans-lithospheric continuum exists whereby post-subduction magmas transporting metal-rich sulfide cargoes play a fundamental role in fluxing metals into the crust from metasomatised lithospheric mantle. Therefore, ore deposits are not merely associated with isolated zones where serendipitous happenstance has produced mineralisation. Rather, they are depositional points along the mantle-to-upper crust pathway of magmas and hydrothermal fluids, synthesising the concentrated metallogenic budget available.
CRIS-Team Scopus Importer:2019-08-13

A Method for Modelling of a Creeping Slope with a Visco-Hypoplastic Material Law - Rohn, Joachim; et al. (Mathematical Geology, 2006)
This paper presents the numerical simulation of a creeping slope in Upper Austria, using a visco-hypoplastic material law which describes the mechanical behavior of cohesive soils allowing for viscous effects, i.e. creep and relaxation. The method consists of: (1) determination of the parameters of the material law, based on laboratory tests on soil samples taken from the slope; (2) simulation of the laboratory tests with an element test program in which the used material law was implemented, in order to test whether the model holds for the soils studied; and (3) simulation of slope movements at different sections along the slope, assuming an infinite slope. The simulation results fit well with the field measurements. This demonstrates that despite strongly simplified boundary conditions and limited availability of subsurface data (e.g. density) the visco-hypoplastic law is a promising tool for predicting creep movements. © Springer Science+Business Media, Inc. 2006.
UnivIS-Import:2015-03-09:Pub.2006.nat.dgeo.IGM.profes_3.ametho
Keywords: Creeping slope; Upper Austria; Visco-hypoplastic law

A mild and efficient procedure for alkenols oxyselenocyclization by using ionic liquids - Kostic, Marina; Verdia, Pedro; Fernandez-Stefanuto, Veronica; Puchta, Ralph; Tojo, Emilia (Journal of Physical Organic Chemistry, 2019)
A mild and efficient procedure for the oxyselenocyclization of unsaturated alcohols by treatment with phenylselenyl chloride using ionic liquids as solvents/catalyzers has been developed. The reaction proceeds instantaneously under mild conditions with absolute regioselectivity, using primary, secondary, tertiary, and aromatic alcohols, as well as monosubstituted, disubstituted, and trisubstituted alkenols. This procedure provides a new method for the synthesis of substituted tetrahydrofurans and tetrahydropyrans ethers, the precursors of many biologically active metabolites, avoiding the use of toxic and corrosive catalysts. There are no previous reports of selenium-mediated cyclofuncionalization reactions in ionic liquids. Taking into the account the good results obtained with [MMIM][MSO 4 ], its ease preparation, low viscosity, low price, and its capacity to be recovered and reused, it was selected as the solvent/catalyzer. Quantum-chemical calculations (MP2(fc)/6-311 + G**//B3LYP/6-311 + G**) has shown that the intramolecular cyclization is promoted by the hydrogen bond formed between the ionic liquid anion and the hydroxyl group of the alkenol.
CRIS-Team Scopus Importer:2019-05-02
Keywords: catalysis; ionic liquids; oxyselenocyclization; quantum-chemical calculations; sustainable chemistry

A missing piece of the Papio puzzle: Gorongosa baboon phenostructure and intrageneric relationships - Martinez, Felipe I.; Capelli, Cristian; Ferreira da Silva, Maria J.; Aldeias, Vera; Alemseged, Zeresenay; Archer, William; Bamford, Marion; Biro, Dora; Bobe, René; Braun, David R.; Habermann, Jörg; Lüdecke, Tina; et al. (Journal of Human Evolution, 2019)
Most authors recognize six baboon species: hamadryas (Papio hamadryas), Guinea (Papio papio), olive (Papio anubis), yellow (Papio cynocephalus), chacma (Papio ursinus), and Kinda (Papio kindae). However, there is still debate regarding the taxonomic status, phylogenetic relationships, and the amount of gene flow occurring between species. Here, we present ongoing research on baboon morphological diversity in Gorongosa National Park (GNP), located in central Mozambique, south of the Zambezi River, at the southern end of the East African Rift System. The park exhibits outstanding ecological diversity and hosts more than 200 baboon troops. Gorongosa National Park baboons have previously been classified as chacma baboons (P. ursinus). In accordance with this, two mtDNA samples from the park have been placed in the same mtDNA clade as the northern chacma baboons. However, GNP baboons exhibit morphological features common in yellow baboons (e.g., yellow fur color), suggesting that parapatric gene flow between chacma and yellow baboons might have occurred in the past or could be ongoing. We investigated the phenostructure of the Gorongosa baboons using two approaches: 1) description of external phenotypic features, such as coloration and body size, and 2) 3D geometric morphometric analysis of 43 craniofacial landmarks on 11 specimens from Gorongosa compared to a pan-African sample of 352 baboons. The results show that Gorongosa baboons exhibit a mosaic of features shared with southern P. cynocephalus and P. ursinus griseipes. The GNP baboon phenotype fits within a geographic clinal pattern of replacing allotaxa. We put forward the hypothesis of either past and/or ongoing hybridization between the gray-footed chacma and southern yellow baboons in Gorongosa or an isolation-by-distance scenario in which the GNP baboons are geographically and morphologically intermediate. These two scenarios are not mutually exclusive. We highlight the potential of baboons as a useful model to understand speciation and hybridization in early human evolution.
CRIS-Team Scopus Importer:2019-05-02
Keywords: Geometric morphometrics; Gorongosa National Park; Hybridization; Papio cynocephalus; Papio ursinus griseipes; Phylogeography

Ammonites from the latest Aalenian-earliest Bathonian of La Baume (Castellane area, SE France): palaeontology and biostratigraphy - de Baets, Kenneth; Cecca, Fabrizio; Guiomar, Myette; Verniers, Jacques (Swiss Journal of Geosciences, 2008)
Middle Jurassic strata are naturally exposed around the village called La Baume, near Castellane (Alpes de Haute Provence, SE France). We have realized both a detailed log and a bed-by-bed sampling for ammonite biostratigraphy in a 68 metres thick succession of subpelagic marls and limestones ("Calcaires A Zoophycos") that spans the Middle Jurassic from uppermost Aalenian to lowermost Bathonian. The subpelagic succession can be roughly subdivided into three members. Ammonites from the Upper Aalenian Concavum Zone, all Lower Bajocian Zones (Discites Zone, Laeviuscula Zone including Ovale Subzone, Humpriesianum Zone), one Upper Bajocian Zone (Parkinsoni Zone) and probably one lower Bathonian Zone (Zigzag Zone) were found. A major gap of both the Niortense Zone and the Garantiana Zone, which was not previously described, was detected at the boundary between members 2 and 3. The main palaeontological interest of the ammonite fauna from La Baume is the richness and diversity of the family Sonniniidae, which is the subject of a systematic study and figurated along with some biostratigraphically significant forms. Biostratigraphical results and open problems are discussed.
Keywords: ammonites; Aalenian-Bathonian interval; France; biodiversity; taxonomy; biostratigraphy

Ammonium ocean following the end-Permian mass extinction - Sun, Yadong; Zulla, M. J.; Joachimski, Michael; Bond, D. P.G.; Wignall, P. B.; Zhang, Z. T.; Zhang, M. H. (Earth and Planetary Science Letters, 2019)
Keywords: ammonium ocean; Early Triassic; nitrogen cycle; ocean anoxic event

Ammonoideen und Gastropoden aus dem Oberen Toarcium und Unteren Aalenium der Tongrube Mistelgau (Frankenalb) - Schulbert, Christian; Nützel, Alexander (Programm und Kurzfassungen, 2002)
UnivIS-Import:2015-04-16:Pub.2002.nat.dgeo.IGM.LP.ammono

Ammonoid Embryonic Development - de Baets, Kenneth; Landman, Neil; Tanabe, Kazushige (Ammonoid Paleobiology: From anatomy to ecology, 2015)

Ammonoid Intraspecific Variability - de Baets, Kenneth; Bert, Didier; Hoffmann, René; Monnet, Claude; Yacobucci, Margaret M.; Klug, Christian (Ammonoid Paleobiology: From anatomy to ecology, 2015)

Ammonoid Paleobiology: From anatomy to ecology - Klug, Christian; Korn, Dieter; de Baets, Kenneth; Kruta, Isabelle; Mapes, Royal H. (Springer, 2015)
This two-volume work is a testament to the abiding interest and human fascination with ammonites. We offer a new model to explain the morphogenesis of septa and the shell, we explore their habitats by the content of stable isotopes in their shells, we discuss the origin and later evolution of this important clade, and we deliver hypotheses on its demise. The Ammonoidea produced a great number of species that can be used in biostratigraphy and possibly, this is the macrofossil group, which has been used the most for that purpose. Nevertheless, many aspects of their anatomy, mode of life, development or paleobiogeographic distribution are still poorly known. Themes treated are biostratigraphy, paleoecology, paleoenvironment, paleobiogeography, evolution, phylogeny, and ontogeny. Advances such as an explosion of new information about ammonites, new technologies such as isotopic analysis, tomography and virtual paleontology in general, as well as continuous discovery of new fossil finds have given us the opportunity to present a comprehensive and timely "state of the art" compilation. Moreover, it also points the way for future studies to further enhance our understanding of this endlessly fascinating group of organism

Ammonoid Paleobiology: From macroevolution to paleogeography - Klug, Christian; Korn, Dieter; de Baets, Kenneth; Kruta, Isabelle; Mapes, Royal H. (Springer, 2015)
This two-volume work is a testament to the abiding interest and human fascination with ammonites. We offer a new model to explain the morphogenesis of septa and the shell, we explore their habitats by the content of stable isotopes in their shells, we discuss the origin and later evolution of this important clade, and we deliver hypotheses on its demise. The Ammonoidea produced a great number of species that can be used in biostratigraphy and possibly, this is the macrofossil group, which has been used the most for that purpose. Nevertheless, many aspects of their anatomy, mode of life, development or paleobiogeographic distribution are still poorly known. Themes treated are biostratigraphy, paleoecology, paleoenvironment, paleobiogeography, evolution, phylogeny, and ontogeny. Advances such as an explosion of new information about ammonites, new technologies such as isotopic analysis, tomography and virtual paleontology in general, as well as continuous discovery of new fossil finds have given us the opportunity to present a comprehensive and timely "state of the art" compilation. Moreover, it also points the way for future studies to further enhance our understanding of this endlessly fascinating group of organism

AMS in basalts: Is there a need for prior demagnetization? - Schöbel, Stefan; de Wall, Helga; Rolf, Christian (Geophysical Journal International, 2013)
Keywords: Effusive volcanism.; Magnetic fabrics and anisotropy; Rock and mineral magnetism

AMS-NRM interferences in the Deccan basalts: Toward an improved understanding of magnetic fabrics in flood basalts - Schöbel, Stefan; de Wall, Helga (Journal of Geophysical Research. Solid Earth, 2014)
Keywords: AMS; AMS-NRM interference; Deccan LIP; flood basalts; flow direction; magnetic fabric

A multidisciplinary approach for the quantitative provenance analysis of siltstone. Mesozoic Mandawa Basin, southeastern Tanzania - Caracciolo, Luca; Andò, Sergio; Vermeesch, Pieter; Garzanti, Eduardo; McCabe, Ross; Barbarano, Marta; Paleari, Chiara; Rittner, Martin; Pearce, Timothy (Journal of the Geological Society, 2019)
This paper shows how heavy minerals and single-grain varietal studies can be conducted on silt (representing 50% of world’s sediments) sediments to obtain quantitative data as efficiently as for sand-sized sediments. The analytical workflows include heavy mineral separation using a wide grain-size window (15-355 μ) analysed through integrated optical analysis, RAMAN spectroscopy, QEMSCAN microscopy, U-Pb dating of detrital zircon. Upper Jurassic-Cretaceous silt-sized sediments from the Mandawa basin of central-southern Tanzania have been selected for the scope of this research. Raman-aided heavy mineral analysis reveals garnet and apatite to be the most common minerals together with durable zircon, tourmaline and subordinate rutile. Accessory but diagnostic phases are titanite, staurolite, epidote, and monazite. Etch pits on garnet and cockscomb features on staurolite document the significant effect of diagenesis on the pristine heavy mineral assemblage. Multivariate statistical analysis highlights a close association among durable minerals (zircon, tourmaline and rutile, ZTR) while garnet and apatite plot alone reflecting independence between the three group of variables with garnet increasing in Jurassic samples. Raman data for garnet end-member analysis document different associations between Jurassic (richer in A, Bi and Bii types) and Cretaceous (dominant A, Ci and Cii types) samples. U-Pb dating of detrital zircon and their statistical integration with the above mentioned datasets provide further insights on changes in provenance and/or drainage systems. Metamorphic rocks of the early and late Pan-African orogeny terranes of the Mozambique belt and those of the Irumide Belt acted as main source of sediment during the Jurassic. Cretaceous sediments record a broadening of the drainage system reaching as far as the Usagran-Ubendian Belt and the Tanzanian Archean Craton.<br
Keywords: Provenance analysis; silt sediments; Tanzania; Mandawa Basin

A multistratigraphic approach to pinpoint the Permian-Triassic boundary in continental depositsThe Zechstein–Lower Buntsandstein transition in Germany - Scholze, Frank; Wang, Xu; Kirscher, Uwe; Kraft, Johannes; Schneider, Jörg W.; Götz, Annette E.; Joachimski, Michael; Bachtadse, Valerian (Global and Planetary Change, 2017)
The Central European Basin is very suitable for high-resolution multistratigraphy of Late Permian to Early Triassic continental deposits. Here the well exposed continuous transition of the lithostratigraphic Zechstein and Buntsandstein Groups of Central Germany was studied for isotope-chemostratigraphy (δC, δC, δO), major and trace element geochemistry, magnetostratigraphy, palynology, and conchostracan biostratigraphy. The analysed material was obtained from both classical key sections (abandoned Nelben clay pit, Caaschwitz quarries, Thale railway cut, abandoned Heinebach clay pit) and a recent drill core section (Caaschwitz 6/2012) spanning the Permian-Triassic boundary. The Zechstein–Buntsandstein transition of Central Germany consists of a complex sedimentary facies comprising sabkha, playa lake, aeolian, and fluvial deposits of predominantly red-coloured siliciclastics and intercalations of lacustrine oolitic limestones. The new data on δC range from − 28.7 to − 21.7 ‰ showing multiple excursions. Most prominent negative shifts correlate with intercalations of oolites and grey-coloured clayey siltstones, while higher δC values correspond to an onset of palaeosol overprint. The δC values range from − 9.7 to − 1.3 ‰ with largest variations recorded in dolomitic nodules from the Zechstein Group. In contrast to sedimentary facies shifts across the Zechstein-Buntsandstein boundary, major element values used as a proxy (CIA, CIA*, CIA-K) for weathering conditions indicate climatic stability. Trace element data used for a geochemical characterization of the Late Permian to Early Triassic transition in Central Germany indicate a decrease in Rb contents at the Zechstein-Buntsandstein boundary. New palynological data obtained from the Caaschwitz quarry section reveal occurrences of Late Permian palynomorphs in the Lower Fulda Formation, while Early Triassic elements were recorded in the upper part of the Upper Fulda Formation. The present study confirms an onset of a normal-polarized magnetozone in the Upper Fulda Formation of the Caaschwitz quarry section supporting an interregional correlation of this crucial stratigraphic interval with the normal magnetic polarity of the basal Early Triassic known from marine sections in other regions. Based on a synthesis of the multistratigraphic data, the Permian-Triassic boundary is proposed to be placed in the lower part of the Upper Fulda Formation, which is biostratigraphically confirmed by the first occurrence date of the Early Triassic Euestheria gutta-Palaeolimnadiopsis vilujensis conchostracan fauna. Rare records of conchostracans reported from the siliciclastic deposits of the lower to middle Zechstein Group may point to its potential for further biostratigraphic subdivision of the Late Permian continental deposits.
Keywords: Biostratigraphy; Central Germany; Conchostraca; Isotope geochemistry; Magnetostratigraphy; Major and trace elements

An 11-yr exclosure experiment in a high-elevation island ecosystem: Introduced herbivore impact on shrub species richness, seedling recruitment and population dynamics - Irl, Severin; Steinbauer, Manuel; Babel, Wolfgang; Beierkuhnlein, Carl; Blume-Werry, Gesche; Messinger, Jana; Palomares Martínez, Angel; Strohmeier, Stefan; Jentsch, Anke (Journal of Vegetation Science, 2012)
Questions: Do introduced herbivores and fire explain the mono-dominance of one legume shrub (Adenocarpus viscosus subsp. spartioides) above the tree line on an oceanic island, given the fact that a number of other legume shrub species are potentially present? What drives the observed landscape-scale life–death pattern within the mono-dominant shrub species population? Location: The sub-alpine scrub vegetation of La Palma (Canary Islands, Atlantic Ocean). Methods: An 11-yr exclosure experiment with sites distributed along an elevation and orientation gradient was used to identify the influence of introduced herbivore pressure on four endemic shrub species and their seedling recruitment. Further, we assessed the population dynamics and spatial pattern of the dominant shrub species A. viscosus subsp. spartioides. Habitat and vitality characteristics were investigated, assessing spatial topographic features and tree ring-based age estimates. Linear mixed models, ANOVAs, linear regression and variation partitioning were used as statistical analysis tools. Results: Outside of the exclosures A. viscosus subsp. spartioides was virtually mono-dominant in the study area, even though other shrub species seem better suited in the absence of introduced herbivores. The presence of introduced herbivores significantly reduced seedling recruitment within all target species, except for A. viscosus subsp. spartioides. Mean age of A. viscosus subsp. spartioides increased with elevation, although vitality analyses indicated that the sub-alpine scrub is elevated above its growth optimum. Three out of four investigated shrub species showed differences in growth height depending on elevation and island orientation. Conclusion: Introduced herbivores and fire are identified as key disturbances enhancing the occurrence of A. viscosus subsp. spartioides, a commonly less competitive species. However, Genista benehoavensis, a single island endemic shrub species, seems to be better adapted to the harsh climate conditions of the sub-alpine scrub in the absence of introduced herbivores than any other shrub species.
Keywords: Alien herbivore; Canary Islands; Competition; European rabbit; Fenced plots; Invasive mammals; Legume shrub; Oceanic island; Shrub community; Summit scrub

An abrupt extinction in the Middle Permian (Capitanian) of the Boreal Realm (Spitsbergen) and its link to anoxia and acidification - Bond, David P. G.; Wignall, Paul B.; Joachimski, Michael; Savov, Ivan; Grasby, Stephen E.; Beauchamp, Benoit; Blomeier, Dierk P. G.; Sun, Yadong; Sun, Yadong (Geological Society of America Bulletin, 2015)

An acid-free method of microfossil extraction from clay-rich lithologies using the surfactant Rewoquat - Jarochowska, Emilia; Tonarová, Petra; Munnecke, Axel; Ferrová, Lenka; Sklenář, Jan; Vodráková, Stanislava (Palaeontologia Electronica, 2013)
Marine rocks characterized by high clay content provide excellent conditions for fossil preservation, particularly for organic-walled microfossils such as retiolitid graptolites and chitinozoans. Nevertheless, the phyllosilicate minerals, which constitute the clay component, make microfossil extractions difficult. The problem results from the tendency of phyllosilicates to form aggregates in low pH values, as standard methods of microfossil extraction employ acids for rock digestion. Consequently, the use of acids for clay-rich rocks is often inefficient and time-consuming. We propose a method of rock disintegration using the surfactant Rewoquat and compare it with two commonly applied approaches: digestion in buffered acetic acid and in HCl-HF. Using examples from the Mulde Brick-clay Member from the Silurian of Gotland and the Daleje Shale from the Devonian of the Prague Basin we observed that disintegration in Rewoquat was faster (days) than digestion in acid (months), and allowed to recover calcareous in addition to organic-walled fossils. The yield and preservation was comparably good, except for conodonts, which were strongly etched after using HCl-HF. Retiolitid graptolites recovered using Rewoquat were preserved in 3D and showed a lower degree of fragmentation. The fossil content of the residue obtained using Rewoquat was higher due to dispersion of clay aggregates. For observation of delicate fossils we recommend to coat the sample with the surfactant. Application of Rewoquat can reveal the most delicate forms and growth stages, and thus provide a better insight into the ontogeny, autecology, and body size distributions of a number of fossil groups. © Paleontological Society November 2013.
UnivIS-Import:2015-04-14:Pub.2013.nat.dgeo.IGM.LP.anacid
Keywords: Acid digestion; Calcareous; Clay dispersion; Fossils; Microfossils; Organic-walled; Phosphatic; Three-dimensional preservation

Analyses and assessment of the sedimentary record of Lake Mladotice (western Czech Republic) in relation to flood events and pre-to postcommunist change in land use - Schulte, Achim; Alrecht, Mascha; Daut, Gerhard; Wallner, Johannes; Jansky, Bohumir; van Geldern, Robert (Zeitschrift für Geomorphologie, Supplementband, 2006)

Analyses of pre-injection reservoir data for stable carbon isotope trend predictions in CO 2 monitoring: Preparing for CO 2 injection - Myrttinen, Anssi; Becker, Veith; Nowak, M.; Zimmer, M.; Pilz, P.; Barth, Johannes (Environmental Earth Sciences, 2012)

Analysis of septal spacing and septal crowding in Devonian and Carboniferous ammonoids - Beck, Sophie Marie; de Baets, Kenneth; Klug, Christian; Korn, Dieter (Swiss Journal of Palaeontology, 2021)
Septal crowding is widely known as a sign of maturity in conchs of ammonoids and nautiloids. However, reduced septal spacing may also occur as a consequence of adverse ecological conditions. Here, we address the question how septal spacing varied through ontogeny in representatives of some of the major clades of Devonian and Carboniferous ammonoids. We found that the degree of ontogenetic variation is similar between clades and that variation is only weakly linked with conch form. The results show that septal crowding alone is insufficient to identify adulthood in ammonoids; intermediate septal crowding is a common phenomenon and occurs in various growth stages. Changes in septal distances during ontogeny were, in addition to adulthood of the individuals, a passive reaction likely caused by fluctuating environmental conditions.
Keywords: Ammonoidea; Devonian; Carboniferous; Septal distances; Ontogeny

Analysis of thermal performance and drilling costs of borehole heat exchanger (BHE) in a river deposited area - Luo, Jin; Zhang, Yuhao; Rohn, Joachim (Renewable Energy, 2019)
Two of major concerns to the installation of ground source heat pump system (GSHP) are linked to thermal performance and initial costs of borehole heat exchanger (BHE). In a heterogeneous field, both thermal performance and drilling costs of BHE could be varied drastically. In this paper, specific extractable heat and drilling costs of BHE in a river deposited area which contains three terraces is studied. Geological setting of the soil and rock formations was first investigated. Thermo-physical properties of the geological materials were measured to estimate the specific extractable heat of BHE. The drilling cost of BHE was determined by considering the drillability of rock and soil. Both the specific extractable heat and drilling costs of BHEs was investigated. The results show that the specific extractable heat of BHE increases from 45 W/m to 70 W/m and the drilling costs increase also from 33.7 USD/m till 79.7 USD/m from first terrace to the third terrace. Lastly, a parameter that represents the benefit-to-investment of BHE was mapped to display the thermo-economic feasibility for the BHE-based GCHPs installation of the three river terraces.
CRIS-Team Scopus Importer:2019-12-03
Keywords: Borehole heat exchanger (BHE); Drilling costs; Ground source heat pump (GSHP) system; Heterogeneous ground; Thermal performance

Analysis on performance of borehole heat exchanger in a layered subsurface - Luo, Jin; Bayer, Manfred; Prieß, Anna; Xiang, Wei; Rohn, Joachim (Applied Energy, 2014)
Keywords: Borehole heat exchanger (BHE); Ground properties; Ground source heat pump (GSHP) system; Layered subsurface; Numerical model

An assessment of the suitability of individual rhythmic carbonate successions for astrochronological application - Westphal, Hildegard; Hilgen, Frits; Munnecke, Axel (Earth-Science Reviews, 2010)
A manual is presented to assist in assessing the suitability of individual calcareous rhythmites for high-resolution stratigraphic applications and orbital dating. While the astrochronological approach offers an unprecedented high temporal resolution for stratigraphy, caution is required to carefully choose suitable rhythmites for the analysis. Diagenesis is known to distort or mimic primary signals in particular in carbonate rhythmites. To keep orbital dating a reliable method, the choice of sedimentary successions has to be undertaken with utmost scrutiny. Here, we review and evaluate the methods that have been used for assessing the record of primary signals in calcareous rhythmites. The goal is to provide the orbital stratigrapher with tools for a straightforward and systematic assessment of such successions. © 2010 Elsevier B.
Keywords: Astrochronology; Chronostratigraphy; Climate archive; Differential diagenesis; GSSP; Orbital forcing

Ancestry, Origin and Early Evolution of Ammonoids - Klug, Christian; Kröger, Björn; Vinther, Jakob; Fuchs, Dirk; de Baets, Kenneth (Ammonoid Paleobiology: From macroevolution to paleogeography, 2015)

Ancient frameworks as modern templates: exploring reef rubble consolidation in an ancient reef system - Godbold, Amanda; James, Chase C.; Kießling, Wolfgang; Hohmann, Niklas; Jarochowska, Emilia; Corsetti, Frank A.; Bottjer, David J. (Proceedings of the Royal Society of London, Series B: Biological Sciences, 2025)
Both natural and human-induced stressors cause reef erosion, resulting in reef rubble formation. When consolidated, the rubble can facilitate reef recovery, sparking interest in artificial rubble stabilization as a method for reef restoration. However, our understanding of the natural processes governing coral reef regeneration within rubble beds is limited. This study examines the regeneration processes within ancient rubble frameworks in a Late Triassic carbonate platform. Results show that Late Triassic rubble environments exhibit successional trajectories similar to contemporary rubble environments. Key organisms such as sponges, calcareous red algae, bryozoans, microbes and scleractinian corals, which are instrumental in the consolidation of modern reef rubble, appear to have played comparable roles during the Late Triassic. The similarities between Late Triassic and modern reef rubble consolidation highlight enduring ecological mechanisms important for reef regeneration. This study deepens our understanding of reef dynamics and offers valuable insights for improving current reef restoration strategies, grounded in time-tested natural processes.
CRIS-Team Scopus Importer:2025-02-21
Keywords: breccia; Late Triassic; reef; reef regeneration; reef rubble

Ancient Reef Traits, a database of trait information for reef-building organisms over the Phanerozoic - Raja Schoob, Nussaibah Begum; Dimitrijevic, Danijela; Krause, Mihaela Cristina; Kießling, Wolfgang (Scientific Data, 2022)
Trait-based approaches are increasingly relevant to understand ecological and evolutionary patterns. A comprehensive trait database for extant reef corals is already available and widely used to reveal vulnerabilities to environmental disturbances including climate change. However, the lack of similar trait compilations for extinct reef builders prevents the derivation of generalities from the fossil record and to address similar questions. Here we present the Ancient Reef Traits Database (ARTD), which aims to compile trait information of various reef-building organisms in one single repository. ARTD contains specimen-level data from both published and unpublished resources. In this first version, we release 15 traits for 505 genera and 1129 species, comprising a dataset of 17,841 trait values of Triassic to mid-Holocene scleractinian corals, the dominant reef-builders in the modern ocean. Other trait data, including for other reef-building organisms, are currently being collated.
CRIS-Team WoS Importer:2022-07-29

An early Hettangian coral reef in southern France: Implications for the end-Triassic reef crisis - Kießling, Wolfgang; Roniewicz, Ewa; Villier, Loic; Léonide, Philippe; Struck, Ulrich (Palaios, 2009)
The oldest known Jurassic coral reef is exposed in the Ardche region of southern France. This reef site, consisting of at least three reefal bodies, is of early Hettangian age and thus immediately postdates the end-Triassic mass extinction, which is well known for its catastrophic effect on reef building. Bulk carbonate carbon isotopes of the limestones below the reef are likely to record environmental perturbations subsequent to the mass extinction. The main reef is surprisingly well developed (20 m in thickness, 200 m in lateral extent) and composed of at least four genera and six species of coralsnot only holdover genera from the Triassic, but also one newly evolved genus (Phacelophyllia), contributed to reef construction. Just like their latest Triassic counterparts, the reef is dominated by phaceloid corals with a considerable contribution of microbialite. The reef predates similarly well developed structures by almost ten million years. The shelf setting of the reef renders it unlikely that refuges around oceanic islands are needed to explain survival of corals across the end-Triassic mass extinction. © 2009 SEPM (Society for Sedimentary Geology).
UnivIS-Import:2015-03-09:Pub.2009.nat.dgeo.IGM.LP.anearl

An easy approach to assess the susceptibility of a landslide by utilizing simple raster overlay methods: A case study on Huangtupo landslide (P.R. China) - Dumperth, Christian; Rohn, Joachim; Fleer, Alexander; Wang Jin-Ge,; Xiang Wei,; Zimmermann, Karsten (Journal of Mountain Science, 2016)
Semi qualitative index based methods using rankings and ratings are commonly used in susceptibility estimations over a wide area. However, generalized ranking and ratings are not applicable for one single landslide. This paper gives an easy and transferable approach to a susceptibility assessment of Huangtupo landslide (P.R. China), using raster addition without taking account for ranking and ratings. Slope, aspect, curvature, location and drainage buffer distance raster data sets have been obtained out of open source digital elevation models using ESRI’s ArcGIS. These conditioning factor raster data sets have been translated into raster data sets including simple yes or no criteria, referring to triggering or not. Subsequently they have been added by raster math to acquire a simple raster overlay map. After that this map is compared to initial displacement measurements, obtained by using a ground based synthetic aperture radar device. Acquired data is recalculated to a raster data set using the same spatial extent, to provide the possibility of comparison of the two raster data sets. The results reveal, that 76.35% of all measured movements occur in areas where raster cells include three or more conditioning factors, indicating that easy raster math operations can lead to satisfying results in local scale. © 2016, Science Press, Institute of Mountain Hazards and Environment, CAS and Springer-Verlag Berlin Heidelberg.

Anetoceratinae (Ammonoidea, Early Devonian) from the Eifel and Harz Mountains (Germany), with a revision of their genera - de Baets, Kenneth; Klug, Christian; Korn, Dieter (Neues Jahrbuch für Geologie und Paläontologie-Abhandlungen, 2009)
"Cyrtoceratites arduennensis", one of the stratigraphically oldest ammonoids and type species of the ambiguously defined genus Anetoceras, was first described from the Eifel Mountains. It has been misinterpreted several times and is here re-described, based on the holotype and additional material from the type area. Anetoceras arduennense (STEININGER, 1853) has a crioconical conch with whorls almost touching the preceding volution. The revision of the subfamily Anetoceratinae leads to the result that only five genera (Metabactrites, Borivites, Ivoites gen. Nov. as a replacement name for Teneroceras, Anetoceras, and Erbenoceras) can be regarded valid, which probably represent a phyletic series.
Keywords: Emsian; Agoniatitina; systematics; Germany; coiling; morphometrics

A new and innovative application of stable oxygen isotope chemistry - Pack, Andreas; Hoernes, Stephan; Göbbels, Matthias (European Journal of Mineralogy, 2003)
UnivIS-Import:2015-03-09:Pub.2003.nat.dgeo.IGM.LM.anewan

A new approach in quantitative in-situ XRD of cement pastes: Correlation of heat flow curves with early hydration reactions - Hesse, Christoph; Götz-Neunhoeffer, Friedlinde; Neubauer, Jürgen (Cement and Concrete Research, 2011)
XRD measurements of the hydration of synthetical cement (SyCem) were used to calculate the resulting heat flow from changes in the phase content. Calculations were performed by application of thermodynamic data. The comparison with data recorded from heat flow calorimetry was in good agreement with the calculated heat flow. The initial maximum of heat flow mainly is caused by the aluminate reaction. During the entire main period the silicate reaction dominates hydration with a high and long first maximum of heat flow. The second but less intense heat flow maximum - only visible as a shoulder in most of the technical cements - can be attributed to an acceleration of the aluminate reaction with the enhanced dissolution of C3A and the final formation of ettringite. Moreover, the investigation showed that the dissolution process of C3A is directly controlled by the availability of the calcium sulfate phases. © 2010 Elsevier Ltd.
UnivIS-Import:2015-03-09:Pub.2011.nat.dgeo.IGM.LM.anewap
Keywords: Calorimetry A; Hydration A; Kinetics A; Thermodynamic Calculations B; X-Ray Diffraction B

A new approach to quantify system efficiency with dissolved oxygen isotopes during engineered growth of Galdieria sulphuraria - Mader, Michael; Schwerna, Philipp; Buchholz, Rainer; van Geldern, Robert; Barth, Johannes (Algal Research, 2017)
The microalgae Galdieria sulphuraria was grown in a first technical approach in a closed system experiment for 29 days. In this time period, 6 separate flasks were sampled for oxygen concentration and their stable isotope ratios (O-18/O-16) in dissolved and headspace phases. The oxygen isotope composition of the water was also analysed as an input for the transfer of its O-18/O-16 ratio to molecular oxygen via production by algae. This photosynthetic transfer of the isotope composition of water was counterbalanced by oxygen consumption that enriched both phases in O-18. For this reason, neither dissolved oxygen nor oxygen in the headspace reached the O-18-depleted oxygen isotope ratio of H2O despite excessive photosynthesis. Oxygen that was produced by photosynthesis accumulated with a yield of 13.96 mmol L-1 in the headspace and with 0.5 mmol L-1 in the fluid phase. This difference was due to rapid degassing of the solution. It was further amplified by preferential consumption of the dissolved O-2 phase. In order to quantify oxygen production and its consumption we determined photosynthesis/respiration (P/R) ratios with a formula that combined O-2 concentrations and its isotope ratios. It revealed a P/R ratio of 7.7 after 11 days. After this it decreased again and moved towards dominance of respiration. With this work our results introduce a new method to monitor the growth and efficiency of algae in controlled experiments.
Keywords: Dissolved oxygen; Stable isotopes; Algae growth; Closed system; Respiration; Galdieria sulphuraria

A new Early Jurassic gastropod from Ellesmere Island, Canadian Arctic – one of the oldest known holoplanktonic gastropods - Nützel, Alexander; Schneider, Simon; Hülse, P; Kelly, SRA; Teichert, Sebastian; Veit, R (Jahrestagung der Paläontologischen Gesellschaft, 2015)

A new interpretation of the sedimentary cover in the western Siljan Ring area, central Sweden, based on seismic data - Juhlin, Christopher; Sturkell, Erik; Ebbestad, Jan Ove; Lehnert, Oliver; Högström, Annette E. S.; Meinhold, Guido (Tectonophysics, 2012)
Two new reflection seismic profiles over the Paleozoic successions of the western part of the Siljan Ring impact structure show a contrasting seismic signature. The more southerly c. 10. km long Mora profile reveals a highly disturbed structure, with only a few kilometers of relatively horizontally layered structures observed. However, interpretations of refracted arrivals in the data, that can be correlated to reflections, indicate the Silurian clastic rocks to be about 200. m thick in the central part of the profile. Weak reflections from about 600. m depth suggest a 400. m thick Ordovician limestone sequence to be present. Cores from the area show a mainly shale lithology for the Silurian and only a thin sequence of Ordovician strata, suggesting a rapid thickening of the Ordovician towards the north. On the more northern c. 12. km Orsa profile clear reflections from the Paleozoic successions are seen along the entire profile, except on the southernmost few kilometers. Based on interpretations of refracted arrivals, the Silurian succession appears to be considerably thinner here, and possibly absent at some locations. The Ordovician is also interpreted to be thinner in this area, with a maximum thickness of about 200-300. m along most of the profile. A deeper reflection from about 2. km within the crystalline basement may represent a dolerite sill. The lack of clear basement reflections on the Mora profile can be attributed to near-surface conditions and the acquisition geometry. The seismic data and recent coring in the area suggest the presence of a deeper paleo-basin towards the southwest with significantly more shales being deposited and the Paleozoic successions being severely disturbed. The shallow coring and seismic data will help form the basis for locating future boreholes for deeper drilling to study impact processes and the Paleozoic evolution of central Sweden. © 2012 Elsevier B.V.
UnivIS-Import:2015-03-09:Pub.2012.nat.dgeo.IGM.LG.anewin
Keywords: Borehole; Impact crater; Ordovician; Reflection seismic; Refraction seismic; Silurian

A new look at ancient reefs - Flügel, Erik; Kießling, Wolfgang (Phanerozoic reef patterns, 2002)
UnivIS-Import:2015-04-20:Pub.2002.nat.dgeo.IGM.LP.anewlo

A new name for Triassic algal species Solenopora concentrica Senowbari-Daryan, Link & Isintek 2006 - Senowbari-Daryan, Baba; Link, Michael; Isintek, Ismail (Facies, 2007)
The Triassic algal species Solenopora concentrica Senowbari-Daryan, Link & Isintek (2006) is renamed to S. isoconcentrica.
UnivIS-Import:2015-04-14:Pub.2007.nat.dgeo.IGM.LP.anewna
Keywords: Triassic; Anisian; Karaburun; Turkey; Algae; Solenopora concentrica; Isoconcentrica

A new Pycnodontid (Actinopterygii) in the late Jurassic of the Solnhofen Archipelago - Kölbl-Ebert, Martina; Ebert, Martin; Schulbert, Christian (Research & Knowledge, 2017)
Pycnodontiformes are an extinct order of Actinopterygian fi shes, present from the Late Triassic (Norian) to the Eocene. With their mostly deep, laterally compressed bodies and comparatively large fi ns, these fi shes were mostly highly manoeuvrable reef fi sh. The genus Macromesodon Blake, 1905 (sensu Poyato-Ariza and Wenz, 2004) is divided again in the genus Macromesodon, with Macromesodon macropterus (Agassiz, 1834) as the only species and the genus Apomesodon Poyato-Ariza and Wenz, 200
Keywords: Fossil Fish; Pycnodontiformes; Late Jurassic; Solnhofen Archipelago

A new species of Conchicolites (Cornulitida, Tentaculita) from the Wenlock of Gotland, Sweden - Vinn, Olev; Jarochowska, Emilia; Munnecke, Axel (Estonian Journal of Earth Sciences, 2014)
A new cornulitid species, Conchicolites crispisulcans sp. nov., is described from the Wenlock of Gotland, Sweden. The undulating edge of C. crispisulcans sp. nov. peristomes is unique among the species of Conchicolites. This undulating peristome edge may reflect the position of setae at the tube aperture. The presence of the undulating peristome edge supports the hypothesis that cornulitids had setae and were probably related to brachiopods.
UnivIS-Import:2015-04-14:Pub.2014.nat.dgeo.IGM.LP.anewsp_5
Keywords: Baltica; Cornulitids; Silurian; Tentaculitoids; Tubeworms

A new species of Tiaracrinus from the latest Emsian of Morocco and its phylogeny - Klug, Christian; de Baets, Kenneth; Naglik, Carole; Waters, Johnny A. (Acta Palaeontologica Polonica, 2014)
We describe a new species of the unusual crinoid Tiaracrinus, T jeanlemenni sp. nov. from the latest Emsian of the famous mudmound locality Hamar Laghdad, Morocco. It differs from the previously known species in the higher number of ribs and the vaulted rib-fields, which is corroborated by the comparison of simple quantitative characters and ratios as well as by the results of a cluster analysis and a Principal Component Analysis. Based on the new material and the published specimens, we discuss the phylogeny of the genus and suggest that T oehlerti and T moravicus represent the ancestral forms of this small clade.
Keywords: Crinoidea; mudmounds; phylogeny; morphometry; symmetry; Devonian; Morocco

A new subdisarticulated machaeridian from the Middle Devonian of China: Insights into taphonomy and taxonomy using X-ray microtomography and 3D-analysis - Gügel, Benjamin; de Baets, Kenneth; Jerjen, Iwan; Schuetz, Philipp; Klug, Christian (Acta Palaeontologica Polonica, 2017)
Machaeridians are an extinct group of armoured annelids, which are mainly known from isolated sclerites present from the Ordovician to the Permian. Based on articulated specimens with preserved soft-tissues and trace fossils, derived machaeridians are interpreted to have an infaunal burrowing mode of life. However, the taphonomy of sclerite associations is still largely unstudied. We herein investigated associated sclerites from the Middle Devonian of China using micro-computer tomography and 3D-analysis. These sclerites belong to a single individual and lie in close proximity. The absence of indications for current alignment, major bioturbation or other processes causing a disarticulation as reflected in the randomly arranged dacryoconarids suggest that the sclerites became disarticulated in the course of the normal decay processes, perhaps aided by scavenging and incomplete burial. The unique morphology of the sclerites indicates that the specimen presented here belongs to a previously undescribed species, which we describe herein as Lepidocoleus kuangguoduni sp. nov.
Keywords: Annelida; Lepidocoleidae; tomography; SPIERS; taphonomy; Devonian; China; Guangxi

A new thalamid sponge from the Upper Triassic (Norian) reef limestones of the Antalya region (Turkey) - Senowbari-Daryan, Baba; Link, Michael (Acta Geologica Hungarica, 1998)
The small thalamid sponge Discosiphonella minima n. sp. is described from four reef block samples at three different localities near Antalaya (southern Turkey). The relationship between Paleozoic and Upper Triassic representatives of Discosiphonella are discussed.
Keywords: Systematic Paleontology; Sponges; Sphinctozoa; Discosiphonella; Upper Triassic; Norian; Antalya; Turkey

A new upper Middle Ordovician–Lower Silurian drillcore standard succession from Borenshult in Östergötland, southern Sweden: 1. Stratigraphical review with regional comparisons - Bergström, Stig M.; Calner, Michael; Lehnert, Oliver; Noor, Amir (Gff, 2011)
UnivIS-Import:2015-03-09:Pub.2011.nat.dgeo.IGM.LG.anewup

A new upper Middle Ordovician-Lower Silurian drillcore standard succession from Borenshult in Östergötland, southern Sweden: 2. Significance of δ 13C chemostratigraphy - Bergstroem, Stig M.; Lehnert, Oliver; Calner, Mikael; Joachimski, Michael (GFF, 2012)
Keywords: δ 13C chemostratigraphy; Borenshult fauna; Guttenberg excursion; Hirnantian excursion; Middle and Upper Ordovician; regional correlation

An exceptionally preserved Carboniferous faunal assemblage from the Buckhorn Asphalt Lagerstätte (Oklahoma, USA) - Seuß, Barbara; Wisshak, Max; Nützel, Alexander; Schulbert, Christian (Annual Meeting of the Paläontologische Gesellschaft,, 2008)
The Pennsylvanian Buckhorn Asphalt Quarry in Oklahoma (USA) is an Impregnation Lagerstätte containing the best-preserved Palaeozoic mollusc fauna in the world. Besides preserved Mg-calcite, microstructures, and early ontogenetic shells, it is the only Late Palaeozoic Lagerstätte with conservation of original aragonite known to date. The outstanding preservation is due to an early impregnation by migrating hydrocarbons intruding the mixed siliciclastic-carbonatic sediments of the Buckhorn Asphalt. Deposition took place during a transgressive-regressive cycle near the coast – indicated by landplant remains and high siliciclastic input. The sediments comprise coarse conglomerates to mudstones, and shell beds. Some sediments in the quarry were probably deposited by mass flows, while others are more or less autochthounous. In total the shelly invertebrate fauna comprises more than 155 species and about 120 genera which is unusual for Late Palaeozoic deposits. This corroborates that aragonite dissolution produces a major bias in the fossil record. However, most mollusc genera in the Buckhorn Asphalt Lagerstätte are known as replaced shells from other Pennsylvanian deposits. According to this the preservation bias via dissolution might be overestimated. The fauna is dominated by molluscs, especially gastropods with more than 50 genera, cephalopods, and bivalves. The faunal assemblage is complemented by foraminiferans, ostracodes, bryozoans, brachiopods, and further fossils in smaller amounts like vertebrate and echinoderm remains. Chaetetids represent the largest benthic macro-organisms at the top of the regressive intervals. The preservation of planktotrophic larval shells indicates a high primary production in the ocean waters of the Buckhorn area - an important information, as remains of producer organisms are generally scarce in Late Palaeozoic deposits. The biodiversity of endolithic biota, as indirectly recorded by bioerosion ichnotaxa in the shells, reveals a total of 18 known ichnospecies and the new ichnotaxon Aurimorpha varia, reflecting the most diverse Palaeozoic microboring assemblage known to date. The ichnocoenosis is dominated by Eurygonum nodosum, Scolecia filosa, and Fascichnus dactylus (all of them are cyanobacterial traces). Further traces are e.g. Fascichnus frutex, Planobola macrogata, and Cavernula coccidia. 17 out of 19 reported ichnospecies are known to neoichnology and are present in similar ichnocoenosis of Recent shallow-euphotic seas showing the longevity of microedolithic taxa and therefore their value as palaeoenvironmental indicators. 2/3 of the recorded ichnotaxa were reported for the first time from the Carboniferou

An (in-)coherent metamorphic evolution of high-P eclogites and their host rocks in the Chinese southwest Tianshan? - Meyer, Melanie; Klemd, Reiner; John, Timm; Gao, Jun; Menneken, Martina (Journal of Metamorphic Geology, 2016)
In the (ultra‐)high‐P–low‐T metamorphic terrane of the Chinese South Tianshan, discontinuous mafic blocks and boudins (former upper oceanic crust) are now embedded in voluminous (mainly metasedimentary) host rocks. Two different models were proposed and relate the occurrence of both high‐P and ultra‐high‐P mafic and metasedimentary rocks to either (i) a tectonic mélange style exhumation, with no exhumation of coherent units, but different lithologies derived from different depths juxtaposed and intermingled during exhumation in the subduction channel, or (ii) the evolution of two coherent metamorphic belts: one with high‐P and the other with ultra‐high‐P conditions. In contrast to most previous studies in the Chinese South Tianshan which focused either on single eclogites or metasedimentary rocks (assumed as representative), this study concentrates on the systematic investigation of both mafic boudins and their immediate sedimentary host rocks, because the investigation of both lithologies and the comparison of their metamorphic evolution is crucial to reconstruct the geodynamical context of the whole (ultra‐)high‐P–low‐T metamorphic complex. Several sample pairs consisting of both lithologies were geochemically investigated and their respective metamorphic evolution was reconstructed using geothermobarometry and thermodynamic modelling. The latter approach considers changes in the mineral assemblage during the metamorphic evolution, as well as changes in mineral composition, which may help to determine the metamorphic history of a rock despite the preservation of critical mineral assemblages. All samples experienced a clockwise P–Tpath with overall maximum P–T conditions of 540–550 °C and 1.9–2.25 GPa for the host rocks, and 555–575 °C and 2.2–2.5 GPa for the eclogites. Peak‐metamorphic temperatures of 525–540 °C of the metasedimentary host rocks were also confirmed by Raman spectroscopy of carbonaceous material. Results from thermobarometry and thermodynamic modelling are consistent with the observation that none of the samples contains mineral relicts indicating UHP conditions (like coesite in garnet) and neither conventional thermobarometry, nor thermodynamical modelling resulted in P–Tconditions in the stability field of coesite. Thus, no evidence of ultra‐high‐P conditions was found. Given that the whole sampled river valley lies within the proposed ‘ultra‐high‐P sub‐belt’ and considering former studies, which showed that at other places within this ‘unit’ both ultra‐high‐P and high‐P rocks are now juxtaposed on a small scale, the formation of the whole (ultra‐)high‐P–low‐T metamorphic belt in the Chinese South Tianshan as a tectonic mélange style exhumation is more convincing than the formation and juxtaposition of two coherent metamorphic units with high‐P and ultra‐high‐Pconditions respectively.<br
Keywords: (U)HP metamorphism; eclogite; P–T path; thermobarometry; Tianshan

An integrated 3D approach to assess the geothermal heat-exchange potential: The case study of western Sicily (southern Italy) - Santilano, Alessandro; Donato, Assunta; Galgaro, Antonio; Montanari, Domenico; Menghini, Antonio; Viezzoli, Andrea; Di Sipio, Eloisa; Destro, Elisa; Manzella, Adele (Renewable Energy, 2016)
Keywords: 3D geological modelling; Airborne electromagnetics; Borehole heat exchangers; Geothermal energy; Ground thermal conductivity; Heat-exchange ground potential

An integrated core-based analysis for the characterization of flow, transport and mineralogical parameters of the Heletz pilot CO2 storage site reservoir - Tatomir, Alexandru Bogdan; Halisch, Matthias; Duschl, Florian; Peche, Aaron; Wiegand, Bettina; Schaffer, Mario; Licha, Tobias; Niemi, Auli; Bensabat, Jacob; Sauter, Martin (International Journal of Greenhouse Gas Control, 2016)
Keywords: μ-CT; Tortuosity; Site characterization; Porosity; Core-analysis; Mineralogy; Permeability; Geological CO2 storage; Heletz sandstone

An international intercomparison of stable carbon isotope composition measurements of dissolved inorganic carbon in seawater - Cheng, L.; Normandeau, C.; Bowden, R.; Doucett, R.; Gallagher, B.; Gillikin, D. P.; Kumamoto, Y.; McKay, J. L.; Middlestead, P.; Ninnemann, U.; Nothaft, D.; Dubinina, E. O.; et al. (Limnology and Oceanography-Methods, 2019)

An island view of endemic rarity—Environmental drivers and consequences for nature conservation - Irl, Severin; Schweiger, Andreas; Medina, Felix; Fernández-Palacios, José Maria; Harter, David; Jentsch, Anke; Provenzale, Antonello; Steinbauer, Manuel; Beierkuhnlein, Carl (Diversity and Distributions, 2017)
Aim: Rarity—an important measure for conservation biogeography—can vary over many orders of magnitude. However, it is unclear which regional-scale abiotic conditions drive processes affecting rarity of endemic species on islands. To support conservation efforts, we (1) assess the main abiotic drivers of endemic rarity, (2) determine how well existing protected areas (PAs) coincide with hotspots of endemic rarity and (3) introduce and evaluate a new hypervolume-based rarity estimator. Location: La Palma (Canary Islands).   Methods: We recorded all present endemic vascular plant species in 1,212 plots covering the entire island. We calculated endemic rarity (corrected range-rarity richness for endemics) using a rarity estimation approach based on kernel density estimations (hypervolume approach). We performed a sensitivity analysis based on multiple linear regressions and relative importance estimations of environmental drivers to estimate the performance of the hypervolume-based rarity estimation compared to standard methods (occurrence frequency, convex hulls, alpha hulls).   Results: Climate variables (mean annual temperature, climatic rarity, precipitation variability) best explained archipelago endemic (AE) and single-island endemic (SIE) rarity. Existing PAs covered the majority of AE and SIE rarity, especially national and natural parks as well as the Natura 2000 sites. In our study system, hypervolumes performed better than standard measures of range size.   Main conclusion: Both AE and SIE rarity on La Palma show a clear spatial pattern, with hotspots of endemic rarity found at high elevations and in rare climates, presumably owing to geographical and climatic constraints and possibly anthropogenic pressure (e.g., land use, introduced herbivores, fire). Areas of high rarity estimates coincide with the distribution and extent of PAs on La Palma, especially since the recent addition of the Natura 2000 sites. The hypervolume approach is a promising tool to estimate species range sizes, and can be applied on all scales where point/plot data are available.
Keywords: conservation biogeography; corrected weighted endemism; endemic plant species; evolutionary pattern; hypervolume; island ecology; Natura 2000; protected areas

Anisotropy of diamagnetic susceptibility in Thassos marble: A comparison between measured and modeled data - Bestmann, Michel; de Wall, Helga; et al. (Journal of Structural Geology, 2000)

A nonlinear model coupling rockfall and rainfall intensity based on a four year measurement in a high Alpine rock wall (Reintal, German Alps) - Krautblatter, Michael; Moser, Michael (Natural Hazards and Earth System Sciences, 2009)

A normal-faulting stress regime in the Bavarian Foreland Molasse Basin? New evidence from detailed analysis of leak-off and formation integrity tests in the greater Munich area, SE-Germany - Drews, Michael; Seithel, Robin; Savvatis, Alexandros; Kohl, Thomas; Stollhofen, Harald (Tectonophysics, 2019)
Leak-off and formation integrity test data from the central part of the Bavarian Foreland Molasse Basin have been investigated in detail to infer information about the stress regime of the Cenozoic basin fill. The detailed analysis of leak-off test data from the Bavarian Foreland Molasse Basin and lithology-dependent analysis of leak-off test and formation integrity data is the first of its kind in a published study. Only test data from shale-rich sequences have been considered. All data yield minimum principal stresses that are smaller than an estimated vertical stress range. In combination with critical stress and frictional equilibrium theory, the data indicate that the stress regime in the greater Munich area and possibly the far-field stress regime of the Bavarian Foreland Molasse Basin are most likely of an extensional nature (normal-faulting stress regime). Under the assumption of frictional equilibrium, a friction coefficient between 0.2 and 0.4 best explains failure in shale-dominated sections of the central part of the Bavarian Foreland Molasse Basin and can be used to estimate the minimum horizontal stress SHmin. However, even in the spatially restricted domain of the greater Munich area the stress regime might vary towards a strike-slip stress regime; most likely in the vicinity of fault zones and/or due to variations in mechanical rock strength. The results of this study have great impact and relevance to improved planning of drilling campaigns, future numerical modelling and the general understanding of the evolution of the Bavarian Foreland Molasse Basin. Additional leak-off tests and extended leak-off tests are recommended to fully unravel the spatial variation and geologic control factors of the stress regime of the entire Bavarian Foreland Molasse Basin.
Keywords: North Alpine Foreland Basin; Bavarian Foreland Molasse Basin; Stress regime; Leak-off test; Minimum principal stress

A novel approach to the analysis of thermal response test (TRT) with interrupted power input - Luo, Jin; Zhang, Yuhao; Tuo, Jiasheng; Xue, Wei; Rohn, Joachim; Baumgärtel, Sebastian (Energies, 2020)
The quality of measuring datasets of the thermal response test (TRT) significantly influences the interpretation of borehole thermal parameters (BTP). A thermal response test with an unstable power input may induce an unacceptable error in the estimation of the borehole thermal parameters. This paper proposes a novel approach to treat the dataset with interrupted power input. In this approach, the test records were segmented into several subsections with a constant time interval of 100 min, 60 min, and 30 min, separately. The quality of each data section was assessed and analyzed. Then, two algorithms, including the continuous algorithm and semi-superposition algorithm, were developed. The results estimated by the linear source model (LSM) were compared with one Thermal response test datasets with a stable power input at the same testing site. It shows that the effects of power interruption during the test can be effectively mitigated by deploying both the continuous and semi-superposition methods. The lowest deviation of the calculated thermal conductivity to a thermal response test with stable power input was 2.8% in the continuous method and 0.9% using the semi-superposition method. Thus, the proposed approaches are effective measures to mitigate the effects of interrupted power input on the interpretation of the thermal properties of the ground.
CRIS-Team Scopus Importer:2020-10-23
Keywords: Borehole thermal parameters; Interrupted power input; Measuring outputs; Thermal response test (TRT)

A novel dendroecological method finds a non-linear relationship between elevation and seasonal growth continuity on an island with trade wind-influenced water availability - Weigel, Robert; Irl, Severin; Treydte, Kerstin; Beierkuhnlein, Carl; Berels, Johanna; Field, Richard; Miranda, José Carlos; Steinbauer, Alana; Steinbauer, Manuel; Jentsch, Anke (AoB Plants, 2019)
Climatic seasonality drives ecosystem processes (e.g. productivity) and influences plant species distribution. However, it is poorly understood how different aspects of seasonality (esp. regarding temperature and precipitation) affect growth continuity of trees in climates with low seasonality because seasonality is often only crudely measured. On islands, exceptionally wide elevational species distribution ranges allow the use of tree rings to identify how growth continuity and climate–growth relationships change with elevation. Here we present a novel dendroecological method to measure stem growth continuity based on annual density fluctuations (ADFs) in tree rings of Pinus canariensis to indicate low climatic seasonality. The species ranges from 300 to more than 2000 m a.s.l. on the trade wind-influenced island of La Palma (Canary Islands), where we measured three decades of tree-ring data of 100 individuals distributed over ten sites along the entire elevational range. The successfully implemented ADF approach revealed a major shift of stem growth continuity across the elevational gradient. In a remarkably clear pattern, stem growth continuity (percentage of ADFs) showed a hump-shaped relationship with elevation reaching a maximum at around 1000 m a.s.l.. Low- to mid-elevation tree growth was positively correlated with the Palmer Drought Severity Index PDSI (indicating aridity) and sea surface temperature (indicating trade wind-influenced moderation of water supply), while high elevation tree growth was positively correlated with winter temperature (indicating a cold induced dormancy period). We conclude that ADFs are a useful method to measure stem growth continuity in low-seasonality climates. Growth of Pinus canariensis on the Canary Islands is more frequently interrupted by winter cold at high elevations and by summer drought at low elevations than in the trade wind-influenced mid elevations, where growth sometimes continues throughout the year. Climate change-associated alterations in trade wind cloud formation might cause non-analogue growth limitations for many unique island specie

A novel multi-scale approach to fault network analysis and visualization: test case Franconian Platform (SE Germany) - Wiest, Johannes; Köhler, Saskia; Köhn, Daniel; Stollhofen, Harald; Dengler, Kathrin; Fazlikhani, Hamed (Journal of Structural Geology, 2025)
Faults are essential to reconstruct geologic histories and their presence (or absence) in the subsurface plays a significant role for many societal issues, such as geothermal energy, carbon, hydrogen and hydrocarbon storage or nuclear waste deposition. In the area of the Permo-Mesozoic Franconian Platform (Northern Bavaria, SE Germany) the existence and properties of faults in the subsurface are poorly known due to limited exposure and lack of geophysical data coverage. To address this issue, we have constructed a new fault network based on stratigraphic offsets identified in a network of 18 cross sections. In this contribution, we present our workflow which allows the effective construction of an internally consistent cross-section network covering a study area of >30,000km2, while representing the geology in high detail. Data input is provided by > 3500 (mostly shallow) wells and >250 high-resolution geological maps, complemented by geophysical surveys and field data. We demonstrate how fault segments and their attributes (e.g., fault type, dip direction, offset, certainty of the interpretation, etc.) can be inferred from the profiles, resulting iteratively in consistent profile and fault networks. While we highlight the non-uniqueness of the interpretation and its restriction to vertical offsets, we demonstrate advantages of the fault network, inferred through this pseudo-3D approach, compared to previously available datasets. We discuss the role of newly identified fault populations for Cretaceous inversion tectonics and Cenozoic rifting. Through the incorporation of basic measures of uncertainty and scale-dependency in the resulting fault model, quantification of the fault network can be achieved. This enables the comparison with independent datasets and different model realizations.
CRIS-Team Scopus Importer:2025-06-20
Keywords: Fault network; Inversion; Modeling; Multi-scale; Uncertainty

Anoxic events in the late Frasnian - causes of the Frasnian-Famennian faunal crisis. - Joachimski, Michael; Buggisch, Werner (Geology, 1993)
Carbon isotope data collected from five Frasnian-Famennian boundary sections in central Europe show two positive δ13C excursions in the late Frasnian ( 367 Ma). Both anomalies coincided with the deposition of the bituminous lower and upper Kellwasser horizons. The carbon isotope patterns indicate two phases of enhanced burial and subsequent recycling of organic carbon. A maximum formation of warm saline waters on the subtropical to tropical epicontinental shelves during late Frasnian transgressive episodes may have induced oceanic oxygen deficits. Variations in the Corg burial rates may have resulted in changes in the CO2 concentrations in the oceans and in the atmosphere, culminating in global climatic changes. It is proposed that the repeated co-occurrences of sea-level fluctuations, anoxic conditions, and global climatic changes during the late Frasnian would affect especially the subtropical to tropical shallow-water communities and reef ecosystems, which were severely affected during the Frasnian-Famennian faunal crisis. -Authors
UnivIS-Import:2015-03-05:Pub.1993.nat.dgeo.IGM.LG.anoxic

Antarctic Bioconstructional Bryozoans from Terra Nova Bay (Ross Sea): Morphology, Skeletal Structures and Biomineralization - Lombardi, Chiara; Kuklinski, Piotr; Spirandelli, Edoardo; Bruzzone, Giorgio; Raiteri, Giancarlo; Bordone, Andrea; Mazzoli, Claudio; López Correa, Matthias; van Geldern, Robert; Plasseraud, Laurent; Thomas, Jérôme; Marin, Frederic (Minerals, 2023)
Among Antarctic bryozoans, some species are able to develop calcitic bioconstructions promoting habitat complexity, but the processes leading to biomineral formation are mostly unknown. The present work investigated three Antarctic bryozoans, from morphological to skeletal features, including the organic matrix associated with the skeleton (SOM). Cellarinella nutti Rogick, 1956 and Reteporella frigida Waters, 1904 were collected in November 2018 from a shallow site (25 m) and Cellarinella njegovanae Rogick, 1956 from a deep site (110 m) at Terra Nova Bay (Ross Sea, Antarctica). Both Cellarinella species showed 5–6 “growth check lines” (gcl) on their laminae. The morphometrical characterization conducted on the growth bands (gb) and zooids, within the band across bands, revealed a variability in length with time (C. nutti: from 4099 µm for gb1 to 1449 µm for gb6; C. njegovanae: from 1974 µm for gb 3 to 7127 µm for gb2). Zooid length varied within gb, from the proximal to the distal part of the bands, but differences also occurred across bands. The shortest zooids ( 625 µm) were found at the proximal part and the longest ( 1190 µm) in the middle part of the gb in C. nutti, whereas in C. njegovanae the shortest zooids ( 660 µm) were found in the distal part and the longest ( 1190 µm) in the proximal part of the gb. Micro-CT analyses indicated the ratio of basal zooidal walls (RbwT gcl/gb) ranged from 3.0 to 4.9 in C. nutti and from 2.3 to 5.9 in C. njegovanae, whereas Reteporella frigida did not form any gcl on either side of the colony. Preliminary characterizations of the SOM for the three species evidenced a mixture of proteins and polysaccharides with properties similar to those of better-known biominerals, in terms of quantity and electrophoretic behavior. In addition, a “lectin fingerprint” has been established for the first time in bryozoans, displaying the presence of chitin or chitin-related saccharides. Understanding the complexity of the processes regulating skeleton formation is a key aspect in comprehending the adaptation of bioconstructional ecosystems and the survival of the associated biodiversity under the future ocean
Keywords: Bryozoa; Antarctica; calcifying ecosystem; growth check lines; zooid morphometrics; skeletal organic matrix (SOM); seawater stable isotopes; climate change

Anthropogenic particle dispersions in topsoils of the Middle Nile Delta: a preliminary study on the contamination around industrial and commercial areas in Egypt - Abu Khatita, Atef M.; de Wall, Helga; Koch, Roman (Environmental Earth Sciences, 2016)
Keywords: Anthropogenic particles; Magnetic spherules; Magnetic susceptibility; Nile Delta; Urban dust

An unusual carbon cycle budget of a small stream in a mountain silicate terrain: The case of the Gravona river (Corsica) - Schubert, Christina; Juhlke, Tobias; Huneau, Frederic; Garel, Emilie; Santoni, Sebastien; Barth, Johannes; van Geldern, Robert (Ecohydrology, 2023)
The current research of carbon cycling in inland waters lacks a sound knowledge of carbon outgassing from small streams. As a consequence, these compartments of the terrestrial water cycle might still be seriously underrepresented in estimates of global carbon transfer budgets from land surfaces. This study investigated carbon sources and sinks of a mountain river in a silicate catchment. For this purpose, the high-relief Gravona river, in the western part of the island of Corsica (France) in the Western Mediterranean, was investigated for field parameters, dissolved inorganic carbon (DIC) and its stable carbon isotopes (δ13CDIC). The source region was characterized by low DIC contents and high δ13CDIC values that decreased further downstream due to increasing soil respiration. Associated increasing DIC concentrations and elevated seasonality in the lower river section also indicated more respiration and subsequent DIC-input by weathering. The aqueous partial pressure (pCO2(aq)) was lowest at the source of the Gravona river and samples from the cold season even showed undersaturation that led to uptake of atmospheric CO2. Further downstream, the seasonality of pCO2(aq) increased and was particularly pronounced near the river mouth where CO2 degassing took place. Average DIC flux along the river was 0.129 Gg C year−1 and was almost equal to CO2 degassing from the river surface with 0.128 Gg C year−1. Our study showed that on an annual basis the river is an overall weak to medium source of CO2 to the atmosphere even though headwater parts of the river seasonally act as CO2 sinks.
CRIS-Team Scopus Importer:2023-02-17
Keywords: carbon cycle; carbon dioxide degassing; river water chemistry; stable isotopes; Western Mediterranean

An unusual microbial-rostroconch assemblage from the Mulde Event (Homerian, middle Silurian) in Podolia, Western Ukraine - Jarochowska, Emilia; Munnecke, Axel; Kozłowski, Wojciech (GFF, 2014)
The Homerian (middle Silurian) Mulde Event is an extinction event affecting hemipelagic organisms associated with a positive stable carbon isotope excursion, and an increased proliferation of microbial deposits. The Event is recorded in the Bagovytsya section (Podolia, Ukraine), representing a carbonate ramp setting in the East European Craton, and recording the δ13Ccarb excursion with values reaching +5.17%. The associated facies include oncolitic beds, mud-mounds and thrombolitic buildups dominated by cyanobacteria and microproblematica with proposed bacterial affinities. The associated faunal assemblage includes a high proportion of rostroconchs and abundant gastropods and trilobites. The co-occurrence of grazing organisms and microbial sediments suggests that the microbial preservation was not caused by decreased grazing rates. © 2014 © 2014 Taylor & Francis.
UnivIS-Import:2015-04-14:Pub.2014.nat.dgeo.IGM.LP.anunus
Keywords: anachronistic facies; Baltica; carbon isotope excursion; East European Craton; lundgreni event; oncoids

An updated ground thermal properties database for GSHP applications - Dalla Santa, Giorgia; Galgaro, Antonio; Sassi, Raffaele; Cultrera, Matteo; Scotton, Paolo; Müller, Johannes; Bertermann, David; Mendrinos, Dimitrios; Pasquali, Riccardo; Perego, Rodolfo; Pera, Sebastian; Di Sipio, Eloisa; et al. (Geothermics, 2020)

Anwendung des Konzeptes der Inneren Barriere" auf industrielle Reststoffe - Neubauer, Jürgen; Pöllmann, Herbert (European Journal of Mineralogy, 1993)
UnivIS-Import:2015-03-05:Pub.1993.nat.dgeo.IGM.LM.anwend

A Paleobiology Database szerepe a modern őslénytani kutatásban - Kocsis, Ádám; Pálfy, József; Sághi, Kristóf (Foldtani Kozlony, 2015)

A pan-European planning basis for estimating the very shallow geothermal energy potentials. - Bertermann, David; Klug, Hermann; Morper-Busch, Lucia (Renewable Energy, 2015)
After the Fukushima nuclear disaster, renewable energy resources have become increasingly important in Europe. Based on available pedological, climatological, topographical, and administrative data sets we analysed the pan-European very shallow geothermal energy potentials (vSGP) on a mapping scale of 1:250,000. International standards and unified spatial processing methods across Europe ensure comparability and seamless visualisation. An open source WebGIS dynamically serves spatially explicit maps of all input and result datasets. The results show unconstrained potential areas for exploitation where the thermal conductivity (W/m*K) varies between 0.8W/m*K and 1.2W/m*K within the soil matrix. Depending on parameters such as grain size distribution and humidity, the highest potentials for vSGP exploitation were found in Liechtenstein, Finland, Iceland, and Norway. With over 50% of the respective country affected, Andorra, Montenegro and Slovenia have the highest values assigned with a limitation for vSGP exploitation. The interactive tool for online searching, discovering and analysing the vSGP provide public, planners, and (non)-governmental organisations with information. This place based modelling approach is considered as an input to the National Renewable Energy Action Plans (NREAPs), contributing to the European Renewable Energy Sources (RES) Directive.
UnivIS-Import:2015-03-09:Pub.2015.nat.dgeo.IGM.LG.apaneu
Keywords: European soil database; Heat transfer; Particle size fraction; Soil water content; Spatial analysis; Thermal conductivity; Geologie; erneuerbare Energiequelle

Aphanitic buildup from the onset of the Mulde Event (Homerian, middle Silurian) at Whitman's Hill, Herefordshire, UK: ultrastructural insights into proposed microbial fabrics - Päßler, Jan-Filip; Jarochowska, Emilia; Ray, David C.; Munnecke, Axel; Worton, Graham J. (Estonian Journal of Earth Sciences, 2014)
A microbial origin has been proposed for matrix-supported, low-diversity buildups reported from different palaeocontinents during the onset of the Mulde positive carbon isotope excursion. We have investigated a small aphanitic buildup from the Lower Quarried Limestone Member of the Much Wenlock Limestone Formation, exposed at Whitman’s Hill (Herefordshire), corresponding to the central part of the Midland Platform (UK). Up to 50% of the rock volume in this buildup consists of mottled micrite. The SEM studies revealed that the micrite is largely detrital and does not show features characteristic of calcareous cyanobacteria or leiolites. The aphanitic character of the buildup is suggested to be controlled by the depositional rate, and the widespread occurrence of matrix-supported reefs in this interval to be driven by a mid-Homerian rapid eustatic transgression.
UnivIS-Import:2015-04-14:Pub.2014.nat.dgeo.IGM.LP.aphani
Keywords: Automicrite; Lower Quarried Limestone Member; Midland Platform; Much Wenlock Limestone Formation; Oncoids; Wenlock Series

A Piranha-like pycnodontiform fish from the Late Jurassic - Kölbl-Ebert, Martina; Ebert, Martin; Bellwood, David R.; Schulbert, Christian (Current Biology, 2018)
Pycnodontiformes are an extinct order of ray-finned fishes from the Triassic to Eocene [1, 2], with a characteristic crushing dentition reflecting a highly specialized diet [3]. However, our discovery of a new pycnodontiform from the Late Jurassic (ca. 152 Ma) Plattenkalk deposits of the Solnhofen Archipelago revealed long, pointed teeth along the vomer and triangular teeth with cutting edges along the prearticulars. This is the earliest evidence of specialized flesh cutting in a ray-finned fish. The dentition pattern, tooth shape, jaw morphology, and mechanics are all indicative of a feeding apparatus suitable for slicing flesh or fins, thus pioneering a new ecological niche. Evidence suggests that it may have exploited aggressive mimicry in a striking parallel to the feeding patterns of modern piranha. Remarkably, fossil fishes recovered from the same deposits as the new pycnodontiform show injuries to fins and fin bases. As a marine piranha-like fish contemporary with dinosaurs, it is the oldest known flesh-eating actinopterygian, revealing remarkable convergent evolution with modern piranhas. Kölbl-Ebert et al. describe a new pycnodontiform fish, Piranhamesodon pinnatomus, from the Jurassic. It has specialized morphological features for cutting flesh, including piranha-like teeth. As a marine fish contemporary with dinosaurs, it is the oldest known flesh-eating ray-finned fish, exhibiting remarkable convergent evolution with piranhas.
UnivIS-Import:2019-08-15:Pub.2018.nat.dgeo.IGM.LP.apiran
Keywords: aggressive mimicry; convergent evolution; functional morphology; Late Jurassic; marine fishes; piranha-like dentition; Piranhamesodon; predation; Pycnodontiformes; Solnhofen Archipelago

A possible link between coral reef success, crustose coralline algae and the evolution of herbivory - Teichert, Sebastian; Steinbauer, Manuel; Kießling, Wolfgang (Scientific Reports, 2020)
Crustose coralline red algae (CCA) play a key role in the consolidation of many modern tropical coral reefs. It is unclear, however, if their function as reef consolidators was equally pronounced in the geological past. Using a comprehensive database on ancient reefs, we show a strong correlation between the presence of CCA and the formation of true coral reefs throughout the last 150 Ma. We investigated if repeated breakdowns in the potential capacity of CCA to spur reef development were associated with sea level, ocean temperature, CO2 concentration, CCA species diversity, and/or the evolution of major herbivore groups. Model results show that the correlation between the occurrence of CCA and the development of true coral reefs increased with CCA diversity and cooler ocean temperatures while the diversification of herbivores had a transient negative effect. The evolution of novel herbivore groups compromised the interaction between CCA and true reef growth at least three times in the investigated time interval. These crises have been overcome by morphological adaptations of CCA.

Application of thermodynamic modeling to predict the stable hydrate phase assemblages in ternary CSA-OPC-anhydrite systems and quantitative verification by QXRD - Wolf, Julian; Jansen, Daniel; Götz-Neunhoeffer, Friedlinde; Neubauer, Jürgen (Cement and Concrete Research, 2020)
Thermodynamic modeling was used to predict the stable hydrate phase assemblages in a ternary CSA-OPC-anhydrite system. On the basis of this modeling, five systems with diverging expected hydrate phases were chosen for experimental examination via QXRD and TGA. The aim of this study was to examine whether and to which extent the predicted equilibrium states are reached after 28 days of hydration. Qualitatively the predicted hydrate phase assemblages were reached for all five systems after 28 d of hydration. When the reaction degrees of the anhydrous phases are taken into account the experimental data fits remarkably well to the thermodynamic model. Additionally, C2S dissolution was found to be the most rapid in straetlingite forming environments.
CRIS-Team Scopus Importer:2019-12-31
Keywords: Hydration products (B); Kinetics (A); Portland cement (D); Sulfoaluminate (D); Thermodynamic calculations (B)

Application of two-dimensional XRD for the characterization of the microstructure of self-leveling compounds - Seifert, Severin; Neubauer, Jürgen; Götz-Neunhoeffer, Friedlinde; Motzet, Hubert (Powder Diffraction, 2009)
The two-dimensional XRD (GADDS) was used to characterize the microstructure of an applied self-leveling compound (SLC). A calcium aluminate cement based SLC was prepared on two different substrates (water absorbent and nonwater absorbent) to determine the vertical distribution of the crystalline phases. The application of the GADDS enables the detection of the phase composition of the hydrating mortar in horizontal slices. Thus the analysis could be carried out in position-sensitive mode at three different areas: near the bottom, in the center, and at the top of the mortar. For investigation of SLCs from the very early hydration stage up to 10 h of hydration, a custom-made in situ sample holder for the measurements was designed and constructed. The combination of the GADDS and the custom-made in situ sample holder provides the possibility to characterize additionally the time-dependent phase composition within the SLC. The nonabsorbent substrate has no effect on the hydration of the binder phases but the absorbent substrate influences the formation of ettringite. In the top layer of the SLC the ettringite content is reduced during the first hours of hydration. The absorbing forces of the substrate lead to migration of the mix water to the substrate. This lack of water results in the reduced formation of ettringite. © 2009 International Centre for Diffraction Dat
UnivIS-Import:2015-03-09:Pub.2009.nat.dgeo.IGM.LM.applic_9
Keywords: Cement hydration; Ettringite; GADDS; In situ XRD; Position-sensitive resolution; Self-leveling compound; Two-dimensional XRD

Application of Water Quality Index as a vulnerability indicator to determine seawater intrusion in unconsolidated sedimentary aquifers in a tropical coastal region of Sri Lanka - Chandrajith, Rohana; Bandara, U. G. Chaminda; Diyabalanage, Saranga; Senaratne, Sachintha; Barth, Johannes (Groundwater for Sustainable Development, 2022)
Coastal freshwater aquifers are under threat and in many cases gradually decline due to climate change and over-extraction of water with the rapidly expanding human activities including agriculture and tourism. In this study, coastal sedimentary aquifer systems in northern Sri Lanka were characterized by integrated approaches such as mass balance calculations, Seawater Mixing Index (SMI) and Water Quality Index (WQI). A total of 34 groundwater samples were collected and analyzed for field parameters (pH, electrical conductivity (EC), dissolved oxygen and temperature) their major ions (Ca2+, Mg2+, Na+, K+, Cl-, SO42−, NO3−, HCO3−) and selected trace elements (Sr, Ba, B) as well as stable water isotopes (δ18OH2O and δ2HH2O). The EC in investigated groundwater samples ranged from 81 to 5690 μS/cm (mean - 1260 μS/cm) and served as the first indication of seawater intrusion. The study region consists of predominantly Ca2+-HCO3− and Na+-Cl- water types indicating freshening and seawater intrusions as revealed by a Hydrogeochemical Facies Evaluation (HFE) diagram. The WQI and SMI approach indicated that in the study region, 50–58% of samples are affected by seawater intrusion. Up to 28% of seawater admixture was noted based on the mass balance calculation using Cl- (0.55–156 meq/L) as a conservative tracer. This result significantly correlates with the calculated WQI (r = +0.944; p < 0.000). Water isotope values indicated that most of the groundwater in the area is recharged directly from precipitation while some samples showed influences of evaporation and also mixing with seawater. In summary, the investigated coastal sedimentary aquifer system in the northern part of Sri Lanka is already severely affected by seawater intrusion. However, as marked by the dissolution of carbonate minerals under the influence of monsoonal rains leads to the freshening of groundwater. This study showed that WQI combined with mass balance calculations is useful in assessing the vulnerability of coastal aquifers in arid and semi-arid regions.
CRIS-Team Scopus Importer:2022-09-09
Keywords: Arid and semi-arid zone aquifers; Hydrogeochemical facies evaluation diagram; Mass balance calculation; Sedimentary aquifers; Water isotopes

Applications of stable water and carbon isotopes in watershed research: Weathering, carbon cycling, and water balances - Schulte, Peter; van Geldern, Robert; Freitag, Heiko; Karim, Ajaz; Negrel, Philippe; Petelet-Giraud, Emmanuelle; Probst, Anne; Probst, Jean-Luc; Telmer, Kevin; Veizer, Jan; Barth, Johannes (Earth-Science Reviews, 2011)

A Practicable Guideline for Predicting the Thermal Conductivity of Unconsolidated Soils - Bertermann, David; Rammler, Mario; Wernsdorfer, Mark; Hagenauer, Hannes (Soil Systems, 2024)
For large infrastructure projects, such as high-voltage underground cables or for evaluating the very shallow geothermal potential (vSGP) of small-scale horizontal geothermal systems, large-scale geothermal collector systems (LSCs), and fifth generation low temperature district heating and cooling networks (5GDHC), the thermal conductivity (λ) of the subsurface is a decisive soil parameter in terms of dimensioning and design. In the planning phase, when direct measurements of the thermal conductivity are not yet available or possible, λ must therefore often be estimated. Various empirical literature models can be used for this purpose, based on the knowledge of bulk density, moisture content, and grain size distribution. In this study, selected models were validated using 59 series of thermal conductivity measurements performed on soil samples taken from different sites in Germany. By considering different soil texture and moisture categories, a practicable guideline in the form of a decision tree, employed by empirical models to calculate the thermal conductivity of unconsolidated soils, was developed. The Hu et al. (2001) model showed the smallest deviations from the measured values for clayey and silty soils, with an RMSE value of 0.20 W/(m∙K). The Markert et al. (2017) model was determined to be the best-fitting model for sandy soils, with an RMSE value of 0.29 W/(m∙K).
CRIS-Team Scopus Importer:2024-07-05
Keywords: fifth generation low temperature district heating and cooling networks (5GDHC); high-voltage underground cables; large-scale geothermal collector system (LSC); model validation; thermal conductivity of soils; very shallow geothermal potential (vSGP)

A preliminary assessment of the symmetry of source composition and melting dynamics across the Azores plume - Beier, Christoph; Turner, Simon; Plank, Terry; White, William (Geochemistry Geophysics Geosystems, 2010)
In order to undertake a preliminary assessment of the extent of symmetry in source composition and melting dynamics in the Azores plume we present new ICP-MS trace element data along with Sr, Nd, Pb, and U-Th-Ra isotope data for samples from the islands Flores and Corvo west of the Mid-Atlantic Ridge. We also present data from a picrite from Faial and new ICP-MS trace element data for 28 basaltic lavas from the eastern Azores Plateau to augment data published previously from these samples. Rare earth element data for primitive lavas (MgO ≥ 5% and Mg # ≥ 60) have La/YbN ∼ 10 and variable Ce and/or Eu anomalies. Multi-incompatible trace element patterns normalized to primitive mantle are convex upward with small negative Th and K ± Pb anomalies. While lavas to the east are characterized by low Nb/Zr and generally lower La/Yb ratios (with the notable exception of eastern So Miguel), lavas from the western islands have slightly higher Nb/Zr and La/Yb inferred to reflect smaller degrees of partial melting. The Sr-Nd-Pb isotope systematics imply that Corvo and Flores sample components which range from an isotopic source commonly found in the Azores (e.g., at the eastern island of Graciosa) to a more depleted, MORB-like mantle sampled at the Mid-Atlantic Ridge. However, in common with uncontaminated samples from São Miguel, the Corvo and Flores samples appear to have slightly lower 230Th excesses and higher La/Yb, Tb/Yb than the other Azores islands or the Mid-Atlantic Ridge samples. The trace element and isotope data indicate a relatively symmetric pattern with distance across the MAR, while U-Th disequilibria, and thus inferred melting dynamics, appear less symmetric. Nevertheless, the data suggest that heterogeneities in source composition do not have a large effect on melting dynamics, at least within the Azores islands. Copyright 2010 by the American Geophysical Union.
UnivIS-Import:2015-03-09:Pub.2010.nat.dgeo.IGM.legeo.apreli
Keywords: Azores; Basalts; Corvo; Flores; Mantle plumes

A preliminary global hydrochemical comparison of lakes and reservoirs - Dordoni, Marlene; Zappalà, Paolo; Barth, Johannes (Frontiers in Water, 2023)
Lakes and reservoirs are important for environmental anthropogenic functions in terms of agriculture and/or settlements. Here we present a first global overview of their chemistry by considering 1,508 water bodies, with data from 485 peer-reviewed publications from 1868 to 2020 and further five online databases. This work focusses on major ions (Ca2+, Mg2+, Na+, K+, (Formula presented.) & (Formula presented.), Cl−, (Formula presented.)) and investigates analogies as well as differences between lakes and reservoirs. We applied a Principal Component Analysis (PCA) to group both types of water bodies and to find differences and similarities. The PCA identified fewer variabilities for major ions in reservoirs than in lakes. Moreover, our analyses showed that lakes generally have more total dissolved solids (TDS). Such higher TDS loads in lakes could result from more diverse (and less controlled) inputs from larger catchments and from longer lasting interactions with thicker internal sediment layers. Global median geochemical compositions identified both reservoirs and lakes as calcium-bicarbonate-type waters. This first synthesis provides a basis for future studies and may serve as the start of a global database on these important water bodies.
CRIS-Team Scopus Importer:2023-03-31
Keywords: geochemistry; lakes; major ions; principal component analysis-PCA; reservoirs

A Python tool to determine the thickness of the hydrate layer around clinker grains using SEM-BSE images - Kleiner, Florian; Becker, Franz; Rößler, Christiane; Ludwig, Horst Michael (Journal of Microscopy, 2024)
To accurately simulate the hydration process of cementitious materials, understanding the growth rate of C-S-H layers around clinker grains is crucial. Nonetheless, the thickness of the hydrate layer shows substantial variation around individual grains, depending on their surrounding. Consequently, it is not feasible to measure hydrate layers manually in a reliable and reproducible manner. To address this challenge, a software has been developed to statistically determine the C-S-H thickness, requiring minimal manual interventions for thresholding and for setting limits like particle size or circularity. This study presents a tool, which automatically identifies suitable clinker grains and and perform statistical measurements of their hydrate layer up to a specimen age of 28 days. The findings reveal a significant increase in the C-S-H layer, starting from 0.45 (Formula presented.) after 1 day and reaching 3.04 (Formula presented.) after 28 days. However, for older specimens, the measurement of the C-S-H layer was not feasible due to limited pore space and clinker grains.
CRIS-Team Scopus Importer:2024-03-15
Keywords: calcium silicate hydrate; hydrate layer; hydration

A Quantitative Provenance Analysis (QPA) Approach to Quantify Controls on Sediment Generation and Sediment Flux in the Upper Reaches of the Magdalena River (Colombia): 1. Natural and Anthropic Controls on the Sand Fraction - Liedel, Stefan; Caracciolo, Luca; Restrepo, Juan Camilo; Weltje, Gert Jan; Lucà, Federica; Beltrán‐Triviño, Alejandro; Restrepo Ángel, Juan Darío (Journal of Geophysical Research F: Earth Surface, 2024)
This study investigates the upper Magdalena river basin (Colombia), which is characterized by tectonic activity, tropical climate, heterogeneous lithological assemblages, and anthropic influence. It aims to comprehend factors controlling sediment generation, flux, and composition by incorporating petrographic data from 27 recent fluvial samples along with geochemistry, geomorphological parameters, historical precipitation, land cover, landsliding and suspended sediment load data. The analysis shows mismatches between sand composition and drainage lithology distribution. A new set of endmember mixing models is presented, quantifying the impacts of erodibility, sand generation potential (related to lithology), and sediment connectivity between hillslopes and river outlets (related to geomorphology). Results show enhanced sediment generation from sedimentary rocks (up to 40%) due to high erodibility, and decreased sediment flux from low- to medium-grade metamorphic rocks (up to 60%) due to controlling morphometric parameters. Overrepresentation of plutonic and high-grade metamorphic rocks and underrepresentation of volcanic rocks (up to 100%) are controlled by mineralogical and textural parameters. Enhanced landsliding activity in areas with volcanic activity occasionally overshadows basin-wide compositional trends driven by morphological and lithological characteristics, as it controls rare overrepresentation of volcanic and low-grade metamorphic detritus in the sand fraction. Sediment retention by hydroelectric dams significantly decreases suspended sediment flux by 30%, while deforestation plays a minor role in sediment flux. This study underscores the importance of coupling sediment generation, geomorphology and the distribution of stochastic events related to seismic activity in any sediment production-focused study and for developing numerical models in Quantitative Provenance Analysis (QPA
Keywords: Sediment generation; Quantitative provenance analysis; Hillslope geomorphology; Index of Connectivity; Anthropogenic effect; Sediment budget

A Quantitative Provenance Analysis (QPA) Approach to Quantify Controls on Sediment Generation and Sediment Flux in the Upper Reaches of the Magdalena River (Colombia): 2. Lithological Control on Contribution to Silt‐ to Clay‐Sized Fractions - Liedel, Stefan; Caracciolo, Luca; Beltrán‐Triviño, Alejandro; Restrepo, Juan Camilo; Restrepo Ángel, Juan Darío; Szczerba, Marek (Journal of Geophysical Research F: Earth Surface, 2024)
The composition of 27 fluvial silt and clay sediments was used in this study to identify and quantify the processes in the upper valley of the Magdalena river in South Colombia. The combination of seismic activity, intense precipitation, and landsliding resulted in limited chemical weathering and a very efficient transfer of weathered products to the transfer zone of both tributary rivers and the main trunk. Inputs from plutonic, high-grade metamorphic, volcanic, and low- to medium-grade metamorphic lithologies vary in coarse silt-sized versus fine silt- and clay-sized sediments, reflecting inherited textural parameters and mineralogy. Plutonic and high-grade metamorphic rocks mostly produce sand-sized sediments, up to two times more than coase silt and up to 10 times more than fine silt to clay. The prevalence of siltstone in the area enhances the contribution of sedimentary rocks to fine silt and clay (up to 50% higher than to sand). Volcanic rocks mainly produce coarse silt (up to 2.5 times more than sand). Low-grade metamorphic detritus is enriched in silt and clay (up to 5–7 times). These findings highlight the critical role of lithology in regulating sediment generation. The study's approach can establish or modify factors modeling lithological control on suspended sediment flux, such as in the BQART equatio
Keywords: Sediment generation; Quantitative provenance analysis; Sediment budget; Lithological control; Linear mixing model; Raman light and heavy mineral analysis

AquaTerra, a new Integrated Project in FP 6: Active since June 2004 - Barth, Johannes; et al. (Land Contamination and Reclamation, 2005)

Aquatic biomarkers record Pleistocene environmental changes at Paleolake Olduvai, Tanzania - Colcord, Devon E.; Shilling, Andrea M.; Freeman, Katherine H.; Njau, Jackson K.; Stanistreet, Ian G.; Stollhofen, Harald; Schick, Kathy D.; Toth, Nicholas; Brassell, Simon C. (Palaeogeography, Palaeoclimatology, Palaeoecology, 2019)
Several hypotheses invoke climatic variability as a driving force for hominin evolution. Thus, high-resolution records of climate and environmental variability from anthropologically significant locations can help test these hypotheses. Sedimentary sequences recovered by the Olduvai Gorge Coring Project (OGCP) help evaluate climatic and environmental changes at Olduvai Gorge, Tanzania through the analyses of various biogeochemical proxies. The stratigraphic sequence of OGCP Core 2A can be correlated with horizons associated with hominins and is chronologically constrained by distinctive dated horizons, such as the Bed I Basalt and Tuff IB. The lacustrine interval from 76.6 to 86.9m depth is ideally suited for high-resolution analyses of biogeochemical proxies as it is rich in organic carbon (> 1%TOC). The hydrogen isotopic composition of nC31 in this interval of OGCP Core 2A records the effects of precession-driven wet-dry cycles on the terrestrial environment that led to alternations between woodland and grassland ecosystems, comparable to those documented by previous investigations of outcrop analogues at Olduvai. Here, we examine stratigraphic variations in the abundance of biomarkers (C28 steradienes, C17 and C23 n-alkanes, C27 and C28 A-norsteranes, fern-8-ene, and chromans) derived from aquatic organisms (algae, cyanobacteria, sponges, macrophytes, etc.) to determine the response of Paleolake Olduvai to climate variability. In general, these aquatic biomarkers reflect the productivity of the lake environment and exhibit the same precession-driven wet-dry cycles recorded by terrestrial biogeochemical signatures. However, they also provide evidence of abrupt (< 300 yr) changes in lake level and corresponding aquatic communities superimposed on the longer-term Milankovitch cycles. Thus, evidence for climatic variability is manifested through the pacing and intensity of changes in both terrestrial and aquatic ecosystems, but the different rates of the responses on land and in the aquatic environment potentially had a complex influence on water and food resources that were important factors for hominin habitation and evolution.<br
Keywords: Biomarkers; Sediment core; Hominin evolution; Lacustrine sediments

Aqueous Calcium Phosphate Cement Inks for 3D Printing - Weichhold, Jan; Pfeiffle, Maximilian; Kade, Juliane C.; Hurle, Katrin; Gbureck, Uwe (Advanced Engineering Materials, 2023)
Mimicking the native properties and architecture of natural bone is a remaining challenge within the field of regenerative medicine. Due to the chemical similarity of calcium phosphate cements (CPCs) to bone mineral, these cements are well studied as potential bone replacement material. Nevertheless, the processing and handling of CPCs into prefabricated pastes with adequate properties for 3D printing has drawbacks due to slow reaction times, limited design freedom, as well as fabrication issues such as filter pressing during ejection through thin nozzles. Herein, an aqueous cement paste containing α-tricalcium phosphate powder is proposed, which is stabilized by sodium pyrophosphate (Na4P2O7·10H2O) as additive. Since high powder loadings within pastes can result in filter pressing during extrusion, various concentrations and molecular weights of hyaluronic acid (HyAc) are added to the cement paste, resulting in reduced filter pressing during 3D extrusion-based printing. These cement pastes are investigated regarding their setting reaction after activation with orthophosphate solution by isothermal calorimetry and X-ray diffraction, as well as their hardening performance using Imeter measurements, while the processability is assessed by extrusion through 1.2 and 0.8 mm cannulas. The 3D-printed structures with appropriate HyAc molecular weight and concentration demonstrate suitable mechanical properties and resolution for clinical application.
CRIS-Team Scopus Importer:2023-09-22
Keywords: 3D printing; calcium phosphate cements; hyaluronic acid; premixed cement pastes

Aqueous CO2 partial pressure, d13CDIC, chlorophyll-a, and dissolved organic carbon as indicators of the carbon cycle in the Lawrence River system - Barth, Johannes; et al. (Terra Nova, 1997)

Aragonite calcite sea effects on calcifying organisms and reefs - Eichenseer, Kilian; Balthasar, Uwe; Smart, Christopher W.; Stander, Julian; Haaga, Kristian A.; Kießling, Wolfgang (Annual Meeting of the Palaeontological Association, 2019)
Phanerozoic changes in the oceanic Mg/Ca ratio and temperature gave rise to alternating episodes of abiotic aragonite and calcite precipitation. These aragonite–calcite sea conditions control the abiotic precipitation of calcium carbonate (CaCO3) polymorphs. Experiments have demonstrated that aragonite–calcite sea conditions affect growth rates and skeletal secretion of some marine calcifiers, but questions remain on how these effects operate on ecological scales. Here we create a Phanerozoic model of aragonite and calcite sea conditions to test whether they affect marine calcification on a global scale. We find that aragonite–calcite sea conditions predict the ecological success of fossil calcifiers relative to their aragonitic or calcitic shell composition during the Ordovician–Middle Jurassic. The loss of coupling between shell mineralogy and environment coincides with the onset of deep sea CaCO3 sedimentation and the advent of the modern carbon cycle. However, preliminary results from the distribution of reefs through time indicate that reef systems are affected differentl

A rare find: protoconch in Cretaceous nerineid “gastropod dinosaurs” - Schulbert, Christian; Nützel, Alexander; Kollmann, Heinz; Kaim, Andrzej (Abstracts of the 90th Annual Meeting of the Paläontologische Gesellschaft, 2019)
Nerineoidea is a very diverse fossil group of mostly high-spired gastropods, some of them quite large and with complex folds and protrusions in the aperture respectively whorls. The family ranges from the Jurassic to the end-Cretaceous mass extinction event so that the group can be referred to as “gastropod dinosaurs”. There are several hundred to a few thousand named species. Despite this high diversity, only very few protoconchs have been reported because nerineoids occur mostly in shallow water mixed siliciclastic/calcareous sediments that are prone to strong diagenetic alteration and are thus not favourable for the preservation of tiny, delicate gastropod protoconchs. We found well-preserved protoconchs in the nerineids Aptyxiella granulata Münster and A. flexuosa (Sowerby) from Cretaceous deposits of the Gosau Group at the Pletzach Alm in Austria. It is a smooth heterostrophic larval shell. The high-spired taxa in question is also well-documented in terms of external shell ornaments and the fold pattern within whorls. The latter are documented by internal moulds as well a micro-ct scans. The new find sheds new light on the discussions of the phylogenetic position of Nerineoidea either close to Tubiferidae (“opisthobranchs”) or Pyramidellidae. The systematic position of nerinid gastropods (Tubiferidae) is supported by the position of the exhalant opening at the posterior end of the aperture as a consequence of the shifting of the pallial cavity to the right side. Furthermore, the parietal and the palatal plaits which obviously had no function in muscle attachment delimit a posterior space proceeding from early ontogenetic whorls to the penultimate whorl. It is opening to the anterior part of the whorl in a narrow slit and is considered as equivalent to the pallial caecum of the Heterobranchia. Besides this morphological distinction, a comparabale diet of these generally large gastropods to that of modern Pyramidellidae seems unlikely.<br
Keywords: Nerineoidea

Arctic rhodolith beds – a biodiverse ecosystem endangered by microplastics? - Teichert, Sebastian; Pyko, Ines Anna; Löder, Martin; Mordek, Marlene; Schulbert, Christian; Wisshak, Max; Laforsch, Christian (Status Conference Research Vessels 2020, 2020)

Arctic rhodolith beds and their environmental controls (Spitsbergen, Norway) - Teichert, Sebastian; Woelkerling, William; Rüggeberg, Andres; Wisshak, Max; Piepenburg, Dieter; Meyerhöfer, Michael; Form, Armin; Freiwald, André (Facies, 2014)
Coralline algae (Corallinales, Rhodophyta) that form rhodoliths are important ecosystem engineers and carbonate producers in many polar coastal habitats. This study deals with rhodolith communities from Floskjeret (78°18′N), Krossfjorden (79°08′N), and Mosselbukta (79°53′N), off Spitsbergen Island, Svalbard Archipelago, Norway. Strong seasonal variations in temperature, salinity, light regime, sea-ice coverage, and turbidity characterize these localities. The coralline algal flora consists of Lithothamnion glaciale and Phymatolithon tenue. Well-developed rhodoliths were recorded between 27 and 47 m water depth, while coralline algal encrustations on lithoclastic cobbles were detected down to 77 m water depth. At all sites, ambient waters were saturated with respect to both aragonite and calcite, and the rhodolith beds were located predominately at dysphotic water depths. The rhodolith-associated macrobenthic fauna included grazing organisms such as chitons and echinoids. With decreasing water depth, the rhodolith pavements were regularly overgrown by non-calcareous Polysiphonia-like red algae. The corallines are thriving and are highly specialized in their adaptations to the physical environment as well as in their interaction with the associated benthic fauna, which is similar to other polar rhodolith communities. The marine environment of Spitsbergen is already affected by a climate-driven ecological regime shift and will lead to an increased borealization in the near future, with presently unpredictable consequences for coralline red algal communities.
UnivIS-Import:2015-03-09:Pub.2014.nat.dgeo.IGM.LP.arctic
Keywords: depth gradient; environmental parameters; Lithothamnion glaciale; Phymatolithon tenue; rhodolith community; seasonality; Spitsbergen

A reconstruction of Turkey's potential natural vegetation using climate indicators - Raja, Nussaïbah Begum; Aydin, Olgu; Cicek, Ihsan; Turkoglu, Necla (Journal of Forestry Research, 2019)
Turkey, containing three of the world's biodiversity hotspots, is a hub for genetic biodiversity. However, the vegetation cover has drastically changed in recent decades as a result of substantial transformations in land-use practices. A map of the potential natural vegetation can be used to represent the biodiversity of a country, and therefore a reference to effectively develop conservation strategies. The multinomial logistic regression is used to simulate the probability of different biomes occurring in the country using elevation, climatological data and natural vegetation data. A correlation test was applied to the climatological data to determine which predictors influence vegetation the most. These were temperature, precipitation, relative humidity and cloudiness. The Ordinary Kriging method was employed to transform the data into the format for the multinomial logistic regression model. The model showed that temperature was the most influencing factor with respect to Turkey's vegetation and distribution follows a similar distribution as the various macroclimates. Broadleaf forests are mostly found in the Black Sea region, which is also the wettest region of the country. The Marmara region is the only other region where there are broadleaf forests. Mixed forests and shrublands are mostly located in Central Anatolia due to the region's low humidity which favours herbaceous flora. Coniferous forests were dominant in the Aegean and Mediterranean regions, attributed to high temperatures.
CRIS-Team WoS Importer:2019-11-15

Are coral reefs victims of their own past success? - Renema, Willem; Pandolfi, John; Kießling, Wolfgang (Science Advances, 2016)
Keywords: anthropogenic stress; climate change; coral; ecology; staghorn coral

A record of ductile syn-intrusional fabrics to post solidification cataclasis: Magnetic fabric analysis of neoproterozoic mirpur and Mt. Abu granitoids, NW India - de Wall, Helga; et al. (Journal of the Geological Society of India, 2010)
Keywords: Anisotropy of magnetic susceptibility; Cataclasis; Mirpur granite; Mt. Abu; Nw india

A remastered external standard method applied to the quantification of early OPC hydration - Jansen, Daniel; Götz-Neunhoeffer, Friedlinde; Stabler, Christopher; Neubauer, Jürgen (Cement and Concrete Research, 2011)
A promising external standard method, first described by O'Connor [15], was used to determine the quantitative phase composition of a hydrating cement paste. On the basis of the data produced we can conclude that the method used is absolutely to be recommended for the examination of OPC pastes, since it displays many advantages in comparison to internal standard methods and other methods. No reaction of the phase alite could be detected during the initial and the induction periods of the cement hydration. Additionally it was found that the cement phases involved in the aluminate reaction (bassanite, gypsum, anhydrite and C3A) react successively. The changes detected in the phase composition of the OPC paste could be assigned to the different periods of OPC hydration. © 2011 Elsevier Ltd. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2011.nat.dgeo.IGM.LM.aremas_7
Keywords: Amorphous material (B); Cement paste (C); Hydration (A); Kinetics (A); X-ray diffraction (B)

A Reply to the Discussion of John Bensted of the Paper: Alinite - Chemical composition, solid solution and hydration behavior - Motzet, Hubert; Pöllmann, Herbert; Neubauer, Jürgen (Cement and Concrete Research, 1995)
UnivIS-Import:2015-03-05:Pub.1995.nat.dgeo.IGM.LM.areply

Are pooled tree ring δ13C and δ18O series reliable climate archives? — A case study of Pinus nigra spp. laricio (Corsica/France). - Szymczak, Sonja; Joachimski, Michael; Bräuning, Achim; Hetzer, Timo; Kuhlemann, Joachim (Chemical Geology, 2012)
Stable carbon and oxygen isotopes in tree rings are considered as reliable climate archives as they provide past environmental information with high resolution. However, recent studies have shown that isotope chronologies may reveal a long-term age trend and be influenced by non-climatic factors as other tree-ring parameters as well. These trends can only be identified in chronologies measured on individual trees but not on pooled sample chronologies consisting of several trees. In order to test whether pooled chronologies from pine trees from the Island of Corsica (Mediterranean/France) can be used for climatic reconstructions, we compared calculated mean values from 5 individual trees with pooled chronologies from the same 5 individuals. Carbon and oxygen isotope chronologies for a 50-year interval with annual resolution and 400 years with decadal resolution were analysed in order to document secular changes in inter-tree variability and to test for age related trends in the isotope ratios. Pooled carbon and oxygen isotope series correspond well to chronologies based on mean values calculated from analyses of individual trees. Inter-tree variability in oxygen isotope ratios is higher than in carbon isotope ratios but remains relatively constant over time. Similarities between the isotope series of individual trees are stronger over the 400-year time scale documenting a common long-term signal in the isotope values. No long-term age related trends are observed. Oxygen isotope values of the juvenile phase are characterised by a remarkable decrease over 40–50 years, interpreted to be related to the less developed root system of the young trees. This age effect can be avoided by not considering the first 50 years from the chronologies. Our results confirm that pooled carbon and oxygen isotope chronologies from Pinus nigra can be used for environmental reconstructions without statistical detrending.
UnivIS-Import:2015-03-09:Pub.2012.nat.dgeo.IGM.LG.arepoo
Keywords: Tree rings; Carbon isotopes; Oxygen isotopes; Pooling; Age trend; Pinus nigra ssp. laricio

A review of CO2 and associated carbon dynamics in headwater streams: A global perspective - Marx, Anne; Dusek, Jaromir; Jankovec, Jakub; Sanda, Martin; Vogel, Tomas; van Geldern, Robert; Hartmann, Jens; Barth, Johannes (Reviews of Geophysics, 2017)
Keywords: Carbon cycle; CO2 outgassing; Headwater catchments; River water chemistry; Stable isotopes

A review of ground investigations for ground source heat pump (GSHP) systems - Luo, Jin; Xiang, Wei; Blum, Philipp; Bertermann, David; Bertermann, David; Rohn, Joachim (Energy and Buildings, 2016)
Keywords: Borehole field; Ground heat exchangers (GHE); Ground source heat pump (GSHP) system; Hydraulic conditions; Thermal properties

A review of methods used for equilibrium isotope fractionation investigations between dissolved inorganic carbon and CO 2 - Myrttinen, Anssi; Becker, Veith; Barth, Johannes (Earth-Science Reviews, 2012)

A review of natural hydrofractures in rocks - Bons, Paul D.; Cao, Dongsheng; De Riese, Tamara; Gonzalez-Esvertit, Eloi; Köhn, Daniel; Naaman, Isaac; Sachau, Till; Tian, He; Gomez-Rivas, Enrique (Geological Magazine, 2022)
Hydrofractures, or hydraulic fractures, are fractures where a significantly elevated fluid pressure played a role in their formation. Natural hydrofractures are abundant in rocks and are often preserved as magmatic dykes or sills, and mineral-filled fractures or mineral veins. However, we focus on the formation and evolution of non-igneous hydrofractures. Here we review the basic theory of the role of fluid pressure in rock failure, showing that both Terzaghi's and Biot's theories can be reconciled if the appropriate boundary conditions are considered. We next discuss the propagation of hydrofractures after initial failure, where networks of hydrofractures may form or hydrofractures may ascend through the crust as mobile hydrofractures. As fractures can form as a result of both tectonic stresses and an elevated fluid pressure, we address the question of how to ascertain whether a fracture is a hydrofracture. We argue that extensional or dilational fractures that formed below c. 2-3 km depth are, under normal circumstances, hydrofractures, but at shallower depth they may, but must not be hydrofractures. Since veins and breccias are often the products of hydrofractures that are left in the geological record, we discuss these and critically assess which vein structures can, and which do not necessarily, indicate hydrofracturing. Hydrofracturing can suddenly and locally change the permeability in a rock by providing new fluid pathways. This can lead to highly dynamic self-organization of crustal-scale fluid flow.
CRIS-Team WoS Importer:2023-01-20

A review of Te and Se systematics in hydrothermal pyrite from precious metal deposits: Insights into ore-forming processes - Keith, Manuel; Smith, Daniel J.; Jenkin, Gawen R. T.; Holwell, David A.; Dye, Matthew D. (Ore Geology Reviews, 2018)

A review of the genetic mechanisms generating igneous charnockite: CO2 flushing and crystal-melt segregation in mushy reservoirs - Zhao, Kai; Xu, Xisheng; Klemd, Reiner; He, Zhenyu; Zhang, Xisong (Earth-Science Reviews, 2023)
Igneous charnockites are high-temperature orthopyroxene-bearing granitoids, which constitute an important part of many high-grade terranes. High temperature (typically >750–800 °C) is considered to be a key factor regarding the formation of igneous charnockites, because orthopyroxene reacts with hydrous melts to form biotite and/or amphibole at low temperatures as predicted by equilibrium phase relations. Microstructural records of igneous charnockites suggest that the hydrous crystallization reaction occurs at near equilibrium conditions. Thus, it remains a puzzling question how orthopyroxene is preserved in granitoids that generally solidify at H2O-saturated solidus temperatures (<700 °C). Here, we synthesize mineralogical, petrological, and geochemical data for 32 charnockite plutons worldwide to evaluate the possible preservation mechanisms of orthopyroxene in granitoids. These igneous charnockites are classified as I-A-S types based on their mineral assemblages and whole-rock compositions. The orthopyroxene crystals in the igneous charnockites systematically have lower Al2O3 contents than those in metamorphic rocks, suggesting a magmatic origin of the former. Magmatic orthopyroxene is possibly preserved by two mechanisms, preventing back-reactions with hydrous melts: one mechanism deduced from fluid-inclusion studies highlights the importance of CO2, which can reduce the H2O activity and elevate the solidus temperature to the stability field of orthopyroxene. Physical constraints on fluid transport suggest that this mechanism is feasible when an orthopyroxene-bearing mushy reservoir is flushed by large amounts (>10–20 vol%) of CO2-rich fluids, which could form a permeable flow through bubble channels in the pore medium and significantly elevate the CO2 content (>1000 ppm at pressures of >0.2 GPa) dissolved in the interstitial melts. Available fluid-inclusion studies suggest that such a mechanism may have played an important role in the formation of some I- and A-type charnockites. Nonetheless, deducing the fluid composition solely from fluid-inclusion studies is ambiguous, since the trapping of fluid inclusions may leave a potentially non-representative record due to the different wetting characteristics of CO2 and H2O, as well as post-trapping grain-boundary migration recrystallisation, favoring the entrapment of CO2-rich inclusions. A further alternative mechanism is to extract hydrous melts from an orthopyroxene-bearing mush, thereby restricting the back-reaction of orthopyroxene during progressive crystallization. Igneous charnockites have maximum P2O5 contents of up to 1.0–1.2 wt% at 55–60 wt% SiO2 and Zr contents of up to >400–600 ppm at 60–65 wt% SiO2. The nonsynchronous variations in P2O5 and Zr contents can best be explained by melt extraction from a mush that saturates apatite earlier than zircon during magma evolution. This process produces apatite- and zircon-rich cumulate charnockites that have significantly higher P2O5 and Zr contents than global orthopyroxene-free granitoids. Many I-A-S type charnockites are believed to have formed through this mechanism and represent cumulate granitoids that had lost a significant amount (>20–40%) of hydrous interstitial melt. Our study reveals that the formation of igneous charnockite depends on extreme magmatic processes such as flushing of large amounts of CO2 or high degree of crystal-melt segregation, and not merely on the high temperature of crystallization. Further studies on igneous charnockite should shed new light on quantifying the carbon flux and understanding the differentiation of the continental crust.
CRIS-Team Scopus Importer:2023-01-20
Keywords: CO; Crystal mush; Crystal-liquid segregation; Igneous charnockite; Orthopyroxene

A revised 87Sr/86Sr curve for the Silurian: Implications for global ocean chemistry and the silurian timescale - Cramer, Bradley D.; Munnecke, Axel; Schofield, David I.; Haase, Karsten; Haase, Alexandra; Munnecke, Axel (Journal of Geology, 2011)
Recent recalibration of the Silurian timescale and improved global chronostratigraphic correlation of Silurian strata significantly altered the Silurian 87Sr/86Sr curve and the temporal extent of available data. Whereas previous Silurian 87Sr/86Sr composites showed a generally monotonic increase throughout the Silurian, revisions to the Silurian timescale now require a major increase in the rate of change in 87Sr/86Sr at or near the onset of the Gorstian Age of the Ludlow Epoch. Similarly, improved chronostratigraphic correlations between Silurian outcrops on Anticosti Island, Canada, and Gotland, Sweden, indicate that the middle part of the Telychian Age, which is roughly 10%-15% of the total duration of the Silurian period, is undersampled and underrepresented in Silurian 87Sr/86Sr composites. A revised Silurian 87Sr/86Sr curve based on 241 new and published analyses confirms the significant increase in the rate of change of 87Sr/86Sr toward more radiogenic values near the base of the Ludlow Series. On the basis of these data, we propose that the rapid trend toward more radiogenic 87Sr/86Sr values is indicative of increased weathering of old sialic crust exposed during the Silurian uplift of portions of Baltica, Laurentia, and Avalonia. Importantly, however, the actual rate of change of 87Sr/86Sr will remain equivocal until the durations of Silurian epochs and ages are better constrained. © 2011 by The University of Chicago. All rights reserved.
UnivIS-Import:2015-04-14:Pub.2011.nat.dgeo.IGM.LP.arevis

A roadmap for island biology: 50 fundamental questions after 50 years of The Theory of Island Biogeography - Patino, Jairo; Whittaker, Robert J.; Borges, Paulo A. V.; Maria Fernandez-Palacios, Jose; Ah-Peng, Claudine; Araujo, Miguel B.; Avila, Sergio P.; Cardoso, Pedro; Cornuault, Josselin; De Boer, Erik J.; De Nascimento, Lea; Gil, Artur; et al. (Journal of Biogeography, 2017)
Aims: The 50th anniversary of the publication of the seminal book, The Theory of Island Biogeography, by Robert H. MacArthur and Edward O. Wilson, is a timely moment to review and identify key research foci that could advance island biology. Here, we take a collaborative horizon-scanning approach to identify 50 fundamental questions for the continued development of the field. Location: Worldwide. Methods: We adapted a well-established methodology of horizon scanning to identify priority research questions in island biology, and initiated it during the Island Biology 2016 conference held in the Azores. A multidisciplinary working group prepared an initial pool of 187 questions. A series of online surveys was then used to refine a list of the 50 top priority questions. The final shortlist was restricted to questions with a broad conceptual scope, and which should be answerable through achievable research approaches. Results: Questions were structured around four broad and partially overlapping island topics, including: (Macro)Ecology and Biogeography, (Macro)Evolution, Community Ecology, and Conservation and Management. These topics were then subdivided according to the following subject areas: global diversity patterns (five questions in total); island ontogeny and past climate change (4); island rules and syndromes (3); island biogeography theory (4); immigration–speciation–extinction dynamics (5); speciation and diversification (4); dispersal and colonization (3); community assembly (6); biotic interactions (2); global change (5); conservation and management policies (5); and invasive alien species (4). Main conclusions: Collectively, this cross-disciplinary set of topics covering the 50 fundamental questions has the potential to stimulate and guide future research in island biology. By covering fields ranging from biogeography, community ecology and evolution to global change, this horizon scan may help to foster the formation of interdisciplinary research networks, enhancing joint efforts to better understand the past, present and future of island biotas.
Keywords: biodiversity conservation; community ecology; extinction; global change; island biogeography theory; island biology; island evolution; island macroecology; research priorities

Arsenian pyrite and cinnabar from active submarine nearshore vents, paleochori bay, milos island, Greece - Voudouris, Panagiotis; Kati, Marianna; Magganas, Andreas; Keith, Manuel; Valsami-Jones, Eugenia; Haase, Karsten; Klemd, Reiner; Nestmeyer, Mark (Minerals, 2021)
Active, shallow-water (2–10 m below sea level) and low temperature (up to 115◦C) hydrothermal venting at Paleochori Bay, nearshore Milos Island, Greece, discharges CO2 and H2S rich vapors (e.g., low-Cl fluid) and high-salinity liquids, which leads to a diverse assemblage of sulfide and alteration phases in an area of approximately 1 km2. Volcaniclastic detritus recovered from the seafloor is cemented by hydrothermal pyrite and marcasite, while semi-massive to massive pyrite-marcasite constitute mounds and chimney-like edifices. Paragenetic relationships indicate deposition of two distinct mineralogical assemblages related to the venting of high-Cl and low-Cl fluids, respectively: (1) colloform As-and Hg-bearing pyrite (Py I), associated with marcasite, calcite, and apatite, as well as (2) porous and/or massive As-rich pyrite (Py II), associated with barite, alunite/jarosite, and late-stage hydrous ferric oxides. Mercury, in the form of cinnabar, occurs within the As-rich pyrite (Py I) layers, usually forming distinct cinnabar-enriched micro-layers. Arsenic in colloform pyrite I shows a negative correlation with S indicating that As1− dominates in the pyrite structure suggesting formation from a relatively reducing As-rich fluid at conditions similar to low-sulfidation epithermal systems. On the contrary, As3+ dominates in the structure of porous to massive pyrite II suggesting deposition from a sulfate-dominated fluid with lower pH and higher fO2. Bulk sulfide data of pyrite-bearing hydrothermal precipitates also show elevated As (up to 2587 ppm) together with various epithermal-type elements, such as Sb (up to 274 ppm), Tl (up to 513 ppm), and Hg (up to 34 ppm) suggesting an epithermal nature for the hydrothermal activity at Paleochori Bay. Textural relationships indicate a contemporaneous deposition of As and Hg, which is suggested to be the result of venting from both high-salinity, liquid-dominated, as well as CO2-and H2S-rich vapor-dominated fluids that formed during fluid boiling. The CO2-and H2S-rich vapor that physically separated during fluid boiling from the high-salinity liquid led to calcite formation upon condensation in seawater together with the precipitation of As-and Hg-bearing pyrite I. This also led to the formation of sulfuric acid, thereby causing leaching and dissolution of primary iron-rich minerals in the volcaniclastic sediments, finally resulting in pyrite II precipitation in association with alunite/jarosite. The Paleochori vents contain the first documented occurrence of cinnabar on the seafloor in the Mediterranean area and provide an important link between offshore hydrothermal activity and the onshore mercuryarsenic mineralizing system on Milos Island. The results of this study therefore demonstrate that metal and metalloid precipitation in shallow-water continental arc environments is controlled by epithermal processes known from their subaerial analogues.
Created from Fastlane, Scopus look-up
Keywords: Boiling; Cinnabar; Low-sulfidation epithermal; Shallow-water hydrothermal activity; Steam-heated alunite; Sulfide mound

Arsenic-poor fluids promote strong As partitioning into pyrite - Kutzschbach, Martin; Dunkel, Frederik; Kusebauch, Christof; Schiperski, Ferry; Börner, Frederik; Drake, Henrik; Klimm, Kevin; Keith, Manuel (Geochimica Et Cosmochimica Acta, 2024)
Pyrite is a ubiquitous sulfide mineral found in diverse geological settings and holds great significance in the formation of Au deposits as well as the safe utilization of groundwater due to its remarkable ability to incorporate substantial amounts of As. However, despite its importance, there remains a dearth of fundamental data on the partitioning of As between pyrite and fluid, which is key for accurately modeling the As distribution in these environments. Here, we present new insights into the partitioning behavior of As between pyrite and fluid at conditions that mimic natural fluid systems. Pyrite was synthesized by replacement of natural siderite in hydrothermal experiments at 200 °C and pH 5 applying a wide range of fluid As concentrations, spanning from 0.001 to 100 µg/g. The As distribution and concentration in synthetic pyrite was analyzed by quantitative LA-ICP-MS mapping providing a high spatial resolution and sensitivity at 2–3 µm image pixel size at a detection limit of ∼1 µg/g at the single pixel scale. Pyrite-fluid partitioning coefficients (DAs(py/fluid)) between synthetic pyrite and experimental fluid agree with previously published data for high fluid As concentrations of 1 µg/g to 100 µg/g (DAs < 2000). However, at low As concentrations in the experimental fluid (<1 µg/g), a steep increase in the DAs(py/fluid) values of up to ∼30,000 was detected, demonstrating even stronger As partitioning into pyrite. This is confirmed by the analyses of natural pyrite that precipitated from As-poor fluids (0.3–0.4 ng/g) within a deep anoxic aquifer in SE Sweden. The discovery holds significant implications for the mobility and scavenging of As, which in turn is important for understanding the formation and fingerprinting of mineral deposits as well as for the secure utilization of groundwater resources.
CRIS-Team Scopus Importer:2024-06-07
Keywords: Arsenic partitioning; Geothermal energy; Groundwater remediation; Hydrothermal systems; Ore deposits; Pyrite; Siderite

Arsenic-rich shallow groundwater in sandy aquifer systems buffered by rising carbonate waters: A geochemical case study from Mannar Island, Sri Lanka - Bandara, Udanekath Chaminda; Diyabalanage, Davindu Saranga; Hanke, Christian; van Geldern, Robert; Chandrajith, Rohana; Barth, Johannes (Science of the Total Environment, 2018)

A second horizon scan of biogeography: Golden ages, Midas touches, and the Red Queen - Dawson, Michael N.; Axmacher, Jan C.; Beierkuhnlein, Carl; Blois, Jessica; Bradley, Bethany A.; Cord, Anna F.; Dengler, Jürgen; He, Kate S.; Heaney, Lawrence R.; Jansson, Roland; Mahecha, Miguel D.; Myers, Corinne; et al. (Frontiers of Biogeography, 2016)
Keywords: Anthropocene; Biodiversity conservation; Birds; Ecoinformatics; Functional diversity; Island biogeography; Macroecology; Mammals; Paleoecology; Phylogenetics; Plants; Species distribution modelling (SDM)

A Sediment Budget of the Upper Kaunertal - Hilger, Ludwig; Dusik, Jana-Marie; Heckmann, Tobias; Haas, Florian; Glira, Philipp; Pfeifer, Norbert; Vehling, Lucas; Rohn, Joachim; Morche, David; Baewert, Henning; Stocker-Waldhuber, Martin; Kuhn, Michael; et al. (Geomorphology of Proglacial Systems: Landform and Sediment Dynamics in Recently Deglaciated Alpine Landscapes, 2019)
This chapter presents the sediment budget of the Upper Kaunertal (Kauner valley, Otztal Alps, Austria) for the years 2012-2014 as obtained in the framework of the PROSA (high-resolution measurements of morphodynamics in rapidly changing PROglacial Systems of the Alps) research project. An important methodological basis of this high-mountain sediment budget is the usage of study area-wide LiDAR data (TLS and ALS) of comparatively high temporal and spatial resolution to measure rates of erosion and deposition, and to regionalize/upscale rates at the local scale. After several billion measurement points and data from fieldwork, mapping, and modeling efforts had been processed and evaluated, it was possible to identify and quantify sediment transfer by all relevant processes at the scale of the 62 km(2) study area. These processes include rockfall of three different magnitude classes, debris flows, avalanches, creep on talus, fluvial processes (hillslopes and main fluvial system), rock glaciers, and glaciers. After a short presentation of the process-specific methods to obtain catchment-wide rates, we discuss process-specific results and the budget. The sediment budget does not only show the relative importance of the mentioned processes and spatial subunits (proglacial vs. non-proglacial) in the Upper Kaunertal. It also gives insight into the importance of high-magnitude events and the configuration of the sediment transport system.
CRIS-Team WoS Importer:2021-10-18
Keywords: PROSA project; Sediment budget; Measurement; Geomorphological map; Regionalisation; Spatial modelling

A sequence stratigraphic model for the Lower Coal Measures (Upper Carboniferous) of the Ruhr District, North-West Germany. - Hampson, Gary; Stollhofen, Harald; Flint, Steve (Sedimentology, 1999)
Upper Carboniferous Coal Measures strata have been interpreted traditionally in terms of cyclothems bounded by marine flooding surfaces (marine bands) and coal seams. Correlation of such cyclothems in an extensive grid of closely spaced coal exploration boreholes provides a robust stratigraphic framework in which to study the Lower Coal Measures (Namurian C-Westphalian A) of the Ruhr district, north-west Germany. Three distinct types of cyclothem are recognized, based on their bounding surfaces and internal facies architecture. (1) Type 1 cyclothems are bounded by marine bands. Each cyclothem comprises a thick (30-80 m), regionally extensive, coarsening-upward delta front succession of interbedded shales, siltstones and sandstones, which may be deeply incised by a major fluvial sandstone complex. The delta front succession is capped by a thin (<1 m), regionally extensive coal seam and an overlying marine band defining the top of the cyclothem. (2) Type 2 cyclothems are bounded by thick ( 1 m), regionally extensive coal seams with few splits. The basal part of a typical cyclothem comprises a thick (15-50 m), widespread, coarsening-upward delta front or lake infill succession consisting of interbedded shales, siltstones and sandstones. Networks of major (>5 km wide, 20-40 m thick), steep-sided, multistorey fluvial sandstone complexes erode deeply into and, in some cases, through these successions and are overlain by the coal seam defining the cyclothem top. (3) Type 3 cyclothems are bounded by regionally extensive coal seam groups, characterized by numerous seam splits on a local (0.1-10 km) scale. Intervening strata vary in thickness (15-60 m) and are characterized by strong local facies variability. Root-penetrated, aggradational floodplain heteroliths pass laterally into single-storey fluvial channel-fill sandstones and coarsening-upward, shallow lake infill successions of interbedded shales, siltstones and sandstones over distances of several hundred metres to a few kilometres. Narrow (<2 km) but thick (20-50 m) multistorey fluvial sandstone complexes are rare, but occur in a few type 3 cyclothems. Several cyclothems are observed to change character from type 1 to type 2 and from type 2 to type 3 up the regional palaeoslope. Consequently, we envisage a model in which each cyclothem type represents a different palaeogeographic belt within the same, idealized delta system, subject to the same allogenic and autogenic controls on facies architecture. Type 1 cyclothems are dominated by deltaic shorelines deposited during a falling stage and lowstand of sea level. Type 2 cyclothems represent the coeval lower delta plain, which was deeply eroded by incised valleys that fed the falling stage and lowstand deltas. Type 3 cyclothems comprise mainly upper delta plain deposits in which the allogenic sea-level control was secondary to autogenic controls on facies architecture. The marine bands, widespread coals and coal seam groups that bound these three cyclothem types record abandonment of the delta system during periods of rapid sea-level rise. The model suggests that the extant cyclothem paradigm does not adequately describe the detailed facies architecture of Lower Coal Measures strata. Instead, these architectures may be better understood within a high-resolution stratigraphic framework incorporating sequence stratigraphic key surfaces, integrated with depositional models derived from analogous Pleistocene-Holocene fluvio-deltaic strata.
UnivIS-Import:2015-03-05:Pub.1999.nat.dgeo.IGM.LG.aseque
Keywords: Coal Measures; Facies architecture; Germany; Sequence stratigraphy

A simpler method of determining beta diversity to address diversity patterns in the Cassian Formation (Triassic, Dolomites) - Roden, Vanessa; Kießling, Wolfgang (Fossils: Key to evolution, stratigraphy and palaeoenvironments - Programme, Abstracts, Field trip guides, 2016)

Assessing accuracy of gas-driven permeability measurements: a comparative study of diverse Hassler-cell and probe permeameter devices. - Filomena, Claudio; Hornung, Jens; Stollhofen, Harald (Solid Earth Discussions, 2013)
Permeability is one of the most important petrophysical parameters to describe the reservoir properties of sedimentary rocks, pertaining to problems in hydrology, geothermics, and hydrocarbon reservoir analysis. Outcrop analogue studies, well core measurements, and individual sample analysis take advantage of a variety of commercially available devices for permeability measurements. Very often, permeability data derived from different devices need to be merged within one study (e.g. outcrop minipermeametry and lab-based core plug measurements). To enhance accuracy of different gas-driven permeability measurements, devicespecific aberrations need to be taken into account. The application of simple one-to-one correlations may draw the wrong picture of permeability trends. For this purpose, transform equations need to be established. This study presents a detailed comparison of permeability data derived from a selection of commonly used Hassler cells and probe permeameters. As a result of individual crossplots, typical aberrations and transform equations are elaborated, which enable corrections for the specific permeameters. Permeability measurements of the commercially available ErgoTech gas permeameter and the TinyPerm II probe permeameter are well-comparable over the entire range of permeability, with R2 = 0.955. Aberrations are mostly identified in the permeability range <10 mD, regarding the TinyPerm II and the minipermeameter/Hassler-cell combination at Darmstadt University, which need to be corrected and standardized. Applying standardizations which consider these aberration intervals strongly improves the comparability of permeability data sets and facilitates the combination of measurement principles. Therefore, the utilization of such correlation tests is highly recommended for all kinds of reservoir studies using integrated permeability databases.
UnivIS-Import:2015-03-09:Pub.2013.nat.dgeo.IGM.LG.assess

Assessing mechanisms of environmental change: Palynological signals across the Late Ludlow (Silurian) positive isotope excursion (δ13C, δ18O) on Gotland, Sweden - Stricanne, Ludovic; Munnecke, Axel; Pross, Jörg (Palaeogeography, Palaeoclimatology, Palaeoecology, 2006)
The Silurian is characterised by strong environmental changes, as indicated by several pronounced positive δC and δO excursions. The mechanisms responsible for these isotopic shifts are a matter of much debate. The purpose of the present study is a quantitative high-resolution evaluation of the palynomorph distribution across the Late Ludlow (Ludfordian) isotope excursion on Gotland. Marine and terrestrial palynomorphs have been chosen as palaeoenvironmental indicators because they are widely distributed and exceptionally well preserved. Moreover, the combined analysis of marine and terrestrial palynomorphs allows the reconstruction of contemporaneous palaeoenvironmental change in the marine and terrestrial realms. To correlate our results with the carbon isotope stratigraphy, we have sampled only localities with published isotope data from diagenetically unaltered brachiopod shells. Our results show that fluctuations in the composition of the acritarch assemblages are closely correlated with the stable isotope development. Low abundances of acritarchs occur in times of high stable isotope values and vice versa, indicating that an increase in marine productivity cannot have been the reason for the positive δC excursion. The results are in good agreement with climatic models for the Silurian assuming alternating humid and arid climatic conditions in low latitudes. Times of high stable isotope values correspond to arid climatic conditions in low latitudes, with low input of terrestrial nutrients resulting in impoverished acritarch and conodont communities, whereas times of low stable isotope values correlate with humid climate, high nutrient input, and abundant and diverse acritarch communities. The major change in acritarch communities took place during the increase of the stable isotope values after hemipelagic planktonic or nektonic organisms (graptolites, conodonts) have been affected. This indicates that environmental changes connected with the stable isotope excursion first affected deeper-water settings and later the photic zone. The absolute abundance of terrestrial spores closely mirrors the marine δC and δO development, showing that both the marine and the terrestrial realm were synchronously affected by the climatic changes. The high abundance of spores during the isotope excursion might be explained by increased aeolian input. © 2005 Elsevier B.V. All rights reserve
Keywords: Acritarchs; Bioevents; Gotland; Ludlow; Palynomorphs; Productivity; Silurian; Spores; Stable isotopes

Assessing moisture sources of precipitation in the Western Pamir Mountains (Tajikistan, Central Asia) using deuterium excess - Juhlke, Tobias; Meier, Christiane; van Geldern, Robert; Vanselow, Kim; Wernicke, Jakob; Baidulloeva, Jamila; Barth, Johannes; Weise, Stephan M. (Tellus B, 2019)
Air moisture of oceanic origin can be subject to long-range transport and could contribute to precipitation at distant places. With ongoing climate change the relationship between water vapour sources and sinks is under constant evolution and plays an important role for water budget assessments. This study analysed monthly integrated and event-based precipitation samples from two field sites in the Western Pamir Mountains (Tajikistan) for stable isotope compositions of oxygen (O-18) and hydrogen (H-2) of water. The aim was to investigate water vapour sources and, in particular, to evaluate contributions of water vapour from the Mediterranean region. The latter has been often postulated as a potential moisture source region for Central Asia. Deuterium excess values (d), that serve as a fingerprint of moisture origin, were below 13 parts per thousand in monthly integrated samples, for most of the year. This indicates a smaller contribution of high Mediterranean moisture (approximate to 20 parts per thousand) to the Western Pamir Mountains than originally expected. A maximum d value of 19 parts per thousand was observed in March, which is not in agreement with the common observation of increased Mediterranean contribution during winter (DJF). A Lagrangian backward trajectory model (HYSPLIT) was applied to infer the general air mass origin for sampled precipitation events. A maximum contribution of western' moisture of 40% was also detected in March, while 40%-60% of moisture that contributed to precipitation events in winter was transported by trajectories that originated from the Northern Indian Ocean.
CRIS-Team WoS Importer:2019-05-07

Assessing the Adequacy of Morphological Models Using Posterior Predictive Simulations - Mulvey, Laura; May, Michael R.; Brown, Jeremy M.; Höhna, Sebastian; Wright, April M.; Warnock, Rachel (Systematic Biology, 2025)
Reconstructing the evolutionary history of different groups of organisms provides insight into how life originated and diversified on Earth. Phylogenetic trees are commonly used to estimate this evolutionary history. Within Bayesian phylogenetics a major step in estimating a tree is in choosing an appropriate model of character evolution. While the most common character data used is molecular sequence data, morphological data remains a vital source of information. The use of morphological characters allows for the incorporation fossil taxa, and despite advances in molecular sequencing, continues to play a significant role in neontology. Moreover, it is the main data source that allows us to unite extinct and extant taxa directly under the same generating process. We therefore require suitable models of morphological character evolution, the most common being the Mk Lewis model. While it is frequently used in both palaeobiology and neontology, it is not known whether the simple Mk substitution model, or any extensions to it, provide a sufficiently good description of the process of morphological evolution. In this study we investigate the impact of different morphological models on empirical tetrapod datasets. Specifically, we compare unpartitioned Mk models with those where characters are partitioned by the number of observed states, both with and without allowing for rate variation across sites and accounting for ascertainment bias. We show that the choice of substitution model has an impact on both topology and branch lengths, highlighting the importance of model choice. Through simulations, we validate the use of the model adequacy approach, posterior predictive simulations, for choosing an appropriate model. Additionally, we compare the performance of model adequacy with Bayesian model selection. We demonstrate how model selection approaches based on marginal likelihoods are not appropriate for choosing between models with partition schemes that vary in character state space (i.e., that vary in Q-matrix state size). Using posterior predictive simulations, we found that current variations of the Mk model are often performing adequately in capturing the evolutionary dynamics that generated our data. We do not find any preference for a particular model extension across multiple datasets, indicating that there is no “one size fits all” when it comes to morphological data and that careful consideration should be given to choosing models of discrete character evolution. By using suitable models of character evolution, we can increase our confidence in our phylogenetic estimates, which should in turn allow us to gain more accurate insights into the evolutionary history of both extinct and extant taxa.
CRIS-Team Scopus Importer:2025-02-28
Keywords: Bayesian phylogenetic analysis; model adequacy; model selection; morphological data; morphological models; palaeobiology

Assessing the fidelity of marine vertebrate microfossil δ18O signatures and their potential for palaeo-ecological and -climatic reconstructions - Roelofs, Brett; Barham, Milo; Cliff, John; Joachimski, Michael; Martin, Laure; Trinajstic, Kate (Palaeogeography, Palaeoclimatology, Palaeoecology, 2017)
Conodont biogenic apatite has become a preferred analytical target for oxygen isotope studies investigating ocean temperature and palaeoclimate changes in the Palaeozoic. Despite the growing application in geochemically-based palaeoenvironmental reconstructions, the paucity or absence of conodont fossils in certain facies necessitates greater flexibility in selection of robust oxygen-bearing compounds for analysis. Vertebrate microfossils (teeth, dermal denticles, spines) offer a potential substitute for conodonts from the middle Palaeozoic. Vertebrate bioapatite is particularly advantageous given a fossil record extending to the present with representatives across freshwater to fully marine environments, thus widening the scope of oxygen isotope studies on bioapatite. However, significant tissue heterogeneity within vertebrates and differential susceptibility of these tissues to diagenetic alteration have been raised as potential problems affecting the reliability of the oxygen isotope ratios as palaeoclimatic proxies. Well-preserved vertebrate microfossils and co-occurring conodont fossils from the Upper Devonian and Lower Carboniferous of the Lennard Shelf, Canning Basin, Western Australia, were analysed using bulk (gas isotope ratio mass spectrometry, GIRMS) and in-situ (secondary ion mass spectrometry, SIMS) methodologies, with the latter technique allowing investigation of specific tissues within vertebrate elements. The δO results may be interpreted in terms of palaeolatitudinally and environmentally sensible palaeo-salinity and -temperature and provide a baseline standard for comparison against vertebrate microfossil δO values. Despite an absence of obvious diagenetic modification, GIRMS of vertebrate denticles yielded δO values depleted in O by 2–4‰ relative to co-occurring conodonts. SIMS analysis of dentine tissues exhibited significant heterogeneity, while hypermineralised tissues in both scales and teeth produced δO values comparable with those of associated conodonts. The susceptibility of permeable phosphatic fossil tissues to microbial activity, fluid interaction and introduction of mineral precipitates post-formation is demonstrated in the dentine of vertebrate microfossils, which showed significant heterogeneity and consistent depletion in O relative to conodonts. The hypermineralised tissues present in both teeth and scales appear resistant to many diagenetic processes and indicate potential for palaeoclimatic reconstructions and palaeoecological investigations.
Keywords: Apatite; GIRMS; Histology; Oxygen-isotopes; SIMS; Temperature

Assessing the usefulness of the isotopic composition of CO2 for leakage monitoring at CO2 storage sites: A review - Mayer, B.; Humez, P.; Becker, V.; Dalkhaa, C.; Rock, L.; Myrttinen, Anssi; Barth, Johannes (International Journal of Greenhouse Gas Control, 2015)

Assessing the utility of death assemblages as reference conditions in a common benthic index (M-AMBI) with simulations - Smith, Jansen; Pruden, Matthew J.; Handley, John C.; Durham, Stephen R.; Dietl, Gregory P. (Geological Society of London, 2023)
Incorporating palaeontological data into the methods and formats already familiar to conservation practitioners may facilitate greater use of palaeontological data in conservation practice. Benthic indices (e.g. Multivariate-AZTI Marine Biotic Index; M-AMBI) already incorporate reference conditions and are a good candidate for integration. In simulations of living communities under constant and changing environmental con-ditions, we evaluate the capacity of death assemblage reference conditions to replicate M-AMBI values when used in place of reference conditions from the final ten generations of the simulation or all five hundred simulated generations. Reference conditions from all death assemblage scenarios successfully replicated correct remediation decisions in the majority of simulation runs with environmental change and stability. Variations in M-AMBI values were due to overestimated species richness and Shannon entropy values in the death assemblages but effects of changes to these parameters varied across scenarios, emphasizing the importance of evaluating multiple metrics. Time averaging was largely beneficial, particularly when environmental change occurred and short-term ecological observations (ten generations) produced incorrect remediation decisions. When the duration of time averaging is known, death assemblages can provide valuable longer-term perspectives with the potential to outperform temporally constrained baseline information from monitoring the living community.
CRIS-Team Scopus Importer:2024-12-16

Assessment of geo-hazards in a rapidly changing landscape: the three Gorges Reservoir Region in China - Strehmel, Alexander; Schoenbrodt-Stitt, Sarah; Buzzo, Giovanni; Dumperth, Christian; Stumpf, Felix; Zimmermann, Karsten; Bieger, Katrin; Behrens, Thorsten; Schmidt, Karsten; Bi, Renneng; Hill, Joachim; Udelhoven, Thomas; et al. (Environmental Earth Sciences, 2015)
Keywords: Diffuse matter inputs; Integrated modeling; Land-use change; Landslides; Soil erosion; Three Gorges Reservoir Region

Assessment of land subsidence mechanisms triggered by dolomitic marble dissolution from hydrogeochemistry and stable isotopes of spring waters - Chandrajith, Rohana; Jayasena, H. A. H.; van Geldern, Robert; Barth, Johannes (Applied Geochemistry, 2015)