11 From the Miogeocline to the Sagebrush Ocean: Life through Time in the Basin and Range Province

Thursday, 13 May 2021
8:30 AM - 12:30 PM
JohnNLouie.com Room

PALEOCLIMATE RECONSTRUCTION AND COMPARISON TO MODERN CLIMATES IN CAPE ESPENBERG ALASKA

Paper number: 11-9
Program: Theme Sessions
Time: 11:10 AM – 11:30 AM

Authors

Abstract

The Arctic is experiencing rapid warming and ecological shifts due to climate change and the compounded effects of polar amplification. There is a paucity of information surrounding the carbon cycling response of Arctic coastal marsh environments to these forces. The Cape Espenberg barrier beach system has been prograding for at least 4000 years, preserving a record of environmental change. This study aims to determine the Arctic carbon and mineral accumulation trends in marsh environments at Cape Espenberg for both paleo (~2500 yrs) and modern timeframes. Analytical analysis through radioisotope (137Cs, 210Pb, and 14C), stable isotope spectrometry (ẟ13C, %C, ẟ15N, %N, and C:N), and dry bulk density (DBD) measurements yield a comprehensive physical and chemical dataset. Preliminary results of DBD, %C, and ẟ13C, agree well with the stratigraphic sequence of the sediment cores. Denser marine sands have isotopically heavier ẟ13C isotopes (-11‰ to -16‰), higher DBD (≥0.5 g/cm3), and lower %C values. Lighter peat materials have isotopically lighter ẟ13C isotopes (-26‰ to -31‰), lower DBD (≤0.5 g/cm3), and higher %C values. The results of this study will contribute towards understanding the dynamism of Arctic coastline mineral and carbon cycling, and can be used to better predict future ecological responses to a warming climate.

Geological Society of America Abstracts with Programs. Vol. 53, No. 4

doi: 10.1130/abs/2021CD-363213

© Copyright 2021 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.