The nature of Ordovician limestone-marl alternations in the Oslo-Asker District (Norway): Witnesses of primary glacio-eustasy or diagenetic rhythms?

Beitrag in einer Fachzeitschrift
(Originalarbeit)


Details zur Publikation

Autorinnen und Autoren: Amberg CEA, Collart T, Salenbien W, Egger LM, Munnecke A, Nielsen AT, Monnet C, Hammer Ø, Vandenbroucke TR
Zeitschrift: Scientific Reports
Verlag: Nature Publishing Group
Jahr der Veröffentlichung: 2016
Band: 6
ISSN: 2045-2322
Sprache: Englisch


Abstract


Ordovician limestone-marl alternations in the Oslo-Asker District have been interpreted as signaling glacio-eustatic lowstands, which would support a prolonged â €œ Early Palaeozoic Icehouseâ €. However, these rhythmites could alternatively reflect differential diagenesis, without sedimentary trigger. Here, we test both hypotheses through one Darriwilian and three Katian sections. Our methodology consists of a bed-by-bed analysis of palynological (chitinozoan) and geochemical (XRF) data, to evaluate whether the limestone/marl couplets reflect an original cyclic signal. The results reveal similar palynomorph assemblages in limestones and marls. Exceptions, which could be interpreted as reflecting palaeoclimatological fluctuations, exist at the species level: Ancyrochitina bornholmensis seems to be more abundant in the marl samples from the lower Frognerkilen Formation on Nakkholmen Island. However, these rare cases where chitinozoans differ between limestone/marl facies are deemed insufficient for the identification of original cyclicity. The geochemical data show a near-perfect correlation between insoluble elements in the limestone and the marls, which indicates a similar composition of the potential precursor sediment, also in the Frognerkilen Formation. This is consistent with the palynological data. Although an original cyclic pattern could still be recorded by other, uninvestigated parameters, our palaeontological and geochemical data combined do not support the presence of such a signal.


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Munnecke, Axel Prof. Dr.
Professur für Paläontologie (Schwerpunkt Faziesanalyse)


Einrichtungen weiterer Autorinnen und Autoren

Duke University
LILLE 1 University - Science and Technology
Ruprecht-Karls-Universität Heidelberg
Universiteit Gent (UGent) / Ghent University
University of Copenhagen
University of Oslo


Forschungsbereiche

Klima und Ressourcen
Forschungsschwerpunkt einer Fakultät: Naturwissenschaftliche Fakultät


Zitierweisen

APA:
Amberg, C.E.A., Collart, T., Salenbien, W., Egger, L.M., Munnecke, A., Nielsen, A.T.,... Vandenbroucke, T.R. (2016). The nature of Ordovician limestone-marl alternations in the Oslo-Asker District (Norway): Witnesses of primary glacio-eustasy or diagenetic rhythms? Scientific Reports, 6. https://dx.doi.org/10.1038/srep18787

MLA:
Amberg, Chloé E. A., et al. "The nature of Ordovician limestone-marl alternations in the Oslo-Asker District (Norway): Witnesses of primary glacio-eustasy or diagenetic rhythms?" Scientific Reports 6 (2016).

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Zuletzt aktualisiert 2019-28-02 um 06:09