| Paper No. 190-6 | ||
| Presentation Time: 8:00 AM-12:00 PM | ||
| SR ISOTOPES AS AN INDICATOR OF GANGES-BRAHMAPUTRA PROVENANCE CHANGES DRIVEN BY SHIFTING SOUTH ASIAN MONSOONS | ||
|
YOUNGS, Penny M. and GOODBRED, Steven L. Jr, Marine Sciences Research Center, Stony Brook University, Stony Brook, NY 11794, youngs@msrc.sunysb.edu Sediments carried by the Ganges-Brahmaputra river system and deposited in the Bengal delta have their main sources in rock outcrops of the Himalayas and Tibetan Plateau. The major rock units of this region each have characteristic Sr-isotope signatures, which can be used to determine the dominant source areas for sediments deposited in the delta. This makes Sr-isotopes a useful tool for determining temporal changes in erosion patterns and sediment provenance for the Ganges and Brahmaputra rivers. During the Late Quaternary, the strength and distribution of the southwest monsoon has varied with regional insolation, resulting in a major precipitation peak in the early Holocene. Downcore variations in Sr-isotope ratios suggest that delta response to such millennial-scale climate changes can be resolved from the stratigraphic record. In this study, 87Sr/86Sr has been measured on borehole samples from Holocene deposits of the Ganges-Brahmaputra delta to determine the effects of shifting monsoon patterns on this sediment dispersal system. These data provide valuable information regarding the short-term response of Himalayan erosion to the changing South Asian monsoon climate. | ||
|
2002 Denver Annual Meeting (October 27-30, 2002)
| ||
| Session No. 190--Booth# 97 Sediments, Clastic (Posters) II: Petrology and Provenance Colorado Convention Center: Exhibit Hall 8:00 AM-12:00 PM, Wednesday, October 30, 2002 | ||
© Copyright 2002 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. | ||