HR: 0800h
AN: H51A-1111 [Abstracts]
TI: Late Quaternary Climate and Provenance Signals of Brahmaputra River Sediments in the Sylhet Basin,
Bangladesh
AU: * Tennant, E J
EM: ejtenn@wm.edu
AF: College of William and Mary
Virginia Institute of Marine Science, 1208 Greate Road, Gloucester Point, VA 23062
AU: Kuehl, S A
EM: kuehl@vims.edu
AF: College of William and Mary
Virginia Institute of Marine Science, 1208 Greate Road, Gloucester Point, VA 23062
AB:
A high-resolution record of Brahmaputra River sediments is investigated from a 200-m borehole record from the Sylhet region
in Bangladesh, a rapidly subsiding tectonic tectonic basin that preserves a nearly continuous Late Quaternary sequence. The
percent abundance of major clay minerals down the core was determined by x-ray diffraction techniques. The ratio of smectite
and kaolinite versus illite and chlorite was calculated as a proxy for the extent of chemical versus physical weathering.
Other mineralogical studies of the Bengal Fan have found a correlation between climate and the record of clay mineralogy in
the sediments (e.g. Debrabrant et al., 1996). Interestingly, this study did not yield such a clear correlation, suggesting
that other factors, such as provenance or weathering, could play an important role in the preservation and hence the climatic
signal as interpreted from clay mineralogy.
DE: 4215 Climate and interannual variability (3309)
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting