T52 New Insights into the History of Life from Novel Techniques

Tuesday, 27 October 2020
10:00 AM - 12:00 PM
Meeting Rooms

NOVEL APPROACHES FOR INTERPRETING DEPOSITIONAL ENVIRONMENTS OF FOSSIL VERTEBRATES

Paper number: T52-8
Program: Technical Sessions
Time: 11:40 AM – 11:50 AM

Authors

Abstract

Grain size distributions provide valuable information on sediment transport and mode of deposition, and reveal important insights into paleoenvironments when other tools may not be available. Laser diffraction granulometry (quantitative grain size analysis) is frequently used in Neogene sediment studies, however, this method is rarely used on samples of Mesozoic age or older, due to challenges of disaggregating material and removing diagenetic cements. Recent advances in chemical disaggregation and serial digestion have made it possible to use this method on older samples.

Here, we use laser diffraction granulometry to quantify the grain size distribution of rock matrix material surrounding several exemplar Mesozoic skeletons from the Gobi Desert. The majority of these specimens come from a single locality, Ukhaa Tolgod, which has produced many exquisite full skeletons of dinosaurs, mammals, and squamates. This method has the potential to reveal fine-scale variations in depositional environments, especially in distinguishing eolian from fluvial, or fluvially reworked aeolian. Application to Gobi fossils elucidates potential differences in burial modes for organisms of different taxonomic groups, such as ornithischian dinosaurs, theropod dinosaurs, squamates and mammals.

Geological Society of America Abstracts with Programs. Vol. 52, No. 6

doi: 10.1130/abs/2020AM-357789

© Copyright 2020 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.