Fast and pervasive diagenetic isotope exchange in foraminifera tests is species-dependent

Autor: Cisneros-Lazaro, Deyanira, Adams, Arthur, Guo, Jinming, Bernard, Sylvain, Baumgartner, Lukas P., Daval, Damien, Baronnet, Alain, Grauby, Olivier, Vennemann, Torsten, Stolarski, Jarosław, Escrig, Stéphane, Meibom, Anders
Přispěvatelé: Ecole Polytechnique Fédérale de Lausanne (EPFL), Research On Carbon-rich Key Samples [IMPMC] (IMPMC_ROCKS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institute of Earth Sciences [Lausanne], Université de Lausanne = University of Lausanne (UNIL), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Polish Academy of Sciences (PAN), Muséum national d'Histoire naturelle (MNHN)
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Nature Communications
Nature Communications, 2022, 13 (1), pp.113. ⟨10.1038/s41467-021-27782-8⟩
Nature Communications, Nature Publishing Group, 2022, 13 (1), pp.113. ⟨10.1038/s41467-021-27782-8⟩
Nature Communications, Vol 13, Iss 1, Pp 1-11 (2022)
Nature Communications, vol. 13, no. 1
ISSN: 2041-1723
DOI: 10.1038/s41467-021-27782-8⟩
Popis: Oxygen isotope compositions of fossil foraminifera tests are commonly used proxies for ocean paleotemperatures, with reconstructions spanning the last 112 million years. However, the isotopic composition of these calcitic tests can be substantially altered during diagenesis without discernible textural changes. Here, we investigate fluid-mediated isotopic exchange in pristine tests of three modern benthic foraminifera species (Ammonia sp., Haynesina germanica, and Amphistegina lessonii) following immersion into an 18O-enriched artificial seawater at 90 °C for hours to days. Reacted tests remain texturally pristine but their bulk oxygen isotope compositions reveal rapid and species-dependent isotopic exchange with the water. NanoSIMS imaging reveals the 3-dimensional intra-test distributions of 18O-enrichment that correlates with test ultra-structure and associated organic matter. Image analysis is used to quantify species level differences in test ultrastructure, which explains the observed species-dependent rates of isotopic exchange. Consequently, even tests considered texturally pristine for paleo-climatic reconstruction purposes may have experienced substantial isotopic exchange; critical paleo-temperature record re-examination is warranted.
Paleoclimate reconstructions commonly use oxygen isotope compositions from fossil foraminifera tests as proxies. Here, the authors show that these tests exchange O-isotopes with surrounding fluids, with implications for paleotemperature records.
Databáze: OpenAIRE
Externí odkaz: