Clumped-isotope-derived climate trends leading up to the end-Cretaceous mass extinction in northwest Europe

Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Geology or Earth and Environmental Sciences, Department of Earth and Environmental Sciences Paleotemperature reconstructions linked to Deccan traps volcanic greenhouse gas emissions and associated feed...

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Bibliographic Details
Main Author: O'Hora, Heidi
Other Authors: Earth and Environmental Sciences, Department of, Ann Arbor
Format: Article in Journal/Newspaper
Language:English
Published: 2021
Subjects:
Online Access:https://hdl.handle.net/2027.42/171489
https://doi.org/10.7302/4001
Description
Summary:Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Geology or Earth and Environmental Sciences, Department of Earth and Environmental Sciences Paleotemperature reconstructions linked to Deccan traps volcanic greenhouse gas emissions and associated feedbacks in the lead-up to the end-Cretaceous meteorite impact and extinction document local and global climate trends during a key interval of geologic history. Here, we present a new clumped-isotope-based paleotemperature record derived from fossil bivalves from the Maastrichtian type region, in southeast Netherlands and northeast Belgium. Clumped isotope data documents a mean temperature of 19.2 3.8 C, consistent with other Maastrichtian temperature estimates, and an average seawater δ18O value of -0.2 0.9‰ VSMOW for the region during the latest Cretaceous (67.1–66.0 Ma). A notable temperature increase at ~66.4 Ma is interpreted to be a regional manifestation of the globally-defined Late Maastrichtian Warming Event, linking Deccan Traps volcanic CO2 emissions prior to the end-Cretaceous extinction to climate change in the Maastricht region. Fluctuating seawater δ18O values coinciding with temperature changes suggest alternating influences of warm, salty southern-sourced waters and cooler, fresher northern-sourced waters from the Arctic Ocean. This new paleotemperature record contributes to the understanding of regional and global climate response to large-scale volcanism and ocean circulation changes leading up to a catastrophic mass extinction. http://deepblue.lib.umich.edu/bitstream/2027.42/171489/1/OHora_Heidi_MS_Thesis_2021.pdf c5a42028-499d-4e85-9fdc-dc71e2baca26 Description of OHora_Heidi_MS_Thesis_2021.pdf : MS thesis SELF