Radiolitid rudists

an underestimated archive for Cretaceous climate reconstruction?

verfasst von

Katharina E. Schmitt, Stefan Huck, Malte Krummacker, Niels J. De Winter, Alexis Godet, Philip Claeys, Ulrich Heimhofer

Abstract

Rudist shells are important archives for palaeoenvironmental reconstructions in the greenhouse world of the Cretaceous. Radiolitids, a family of rudists became very abundant dwellers of the shallow marine carbonate platforms during the Cretaceous. Still, due to the complex structure of their low-Mg calcite outer shell layer, radiolitids are often deemed unsuitable for palaeoenvironmental reconstructions. The aim of this study is to present a combination of petrographic (transmitted light microscopy and cathodoluminescence microscopy) and elemental analyses (high-resolution μXRF and stable isotope) to investigate radiolitid shells for diagenetic alteration and to make them accessible as an archive for environmental conditions during the mid-Cretaceous. Four Eoradiolitites shells were analysed in detail: two right valves (RV), a left valve (LV) with an articulated RV and an isolated LV. Three shell structure types have been identified, including a non-compact, compact and celluloprismatic types. The compact structure type was identified in the LVs while the other two types were observed exclusively in the RVs. Radiolitid shell material composed of the non-compact and the compact structure types can be used as palaeoenvironmental archives as it preserved seasonal signals in both, shell growth structure and isotopic records, while celluloprismatic shell structures are less suitable for reconstructions due to diagenetic alteration. The alternation of dark and light lamellae in both valves, RV and LV, provide information on the intertidal living habitat of the shell-producing organism and its life span.

Organisationseinheit(en)

Institut für Geologie

Externe Organisation(en)

Johannes Gutenberg-Universität Mainz
Spar- und Bauverein eG
Schnack Ingenieurgesellschaft mbH Co. KG
Vrije Universiteit Brussel
University of Texas at San Antonio

Typ

Artikel

Journal

LETHAIA

Band

55

Seiten

1-21

ISSN

0024-1164

Publikationsdatum

12.2022

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Ökologie, Evolution, Verhaltenswissenschaften und Systematik, Paläontologie

Ziele für nachhaltige Entwicklung

SDG 14 – Lebensraum Wasser

Elektronische Version(en)

https://doi.org/10.18261/let.55.4.4 (Zugang: Offen)