HR: 16:45h
AN: C54A-04 [Abstracts]
TI: Chemistry of an Antarctic Subglacial Environment – The role of subglacial geochemical processes in global biogeochemical cycles and quantifying subglacial hydrological processes
AU: * Vogel, S W
EM: svogel@geol.niu.edu
AF: Analytical Center for Climate and Environmental Change - Northern Illinois University, Dept
of Geology and Environmental Geosciences
Northern Illinois University, DeKalb, IL 60115, United States
AU: Tulaczyk, S
EM: tulaczyk@es.ucsc.edu
AF: Dept of Earth Sciences - University of California - Santa Cruz, University of California -
Santa Cruz
Earth Sciences
E&MS Bldg
1156 High Street, Santa Cruz, Ca 95064, United States
AU: Lanoil, B D
EM: brian.lanoil@ucr.edu
AF: Dept. of Environmental Sciences - University of California Riversid, Dept. of Environmental
Sciences
University of California Riverside, Riverside, Ca 92521, United States
AB:
It is well known that subglacial environments especially the availability of basal water plays an important role for
the dynamic of ice sheets. Hydrological processes however are far from being understood as direct observations
are hampered through kilometer thick ice. Over the past years, it also has become more and more evident that
despite the cold and isolation wet subglacial environments provide a viable habitat for life. Geochemical and
biogeochemical processes in the sub ice environment not only can create and release chemical compounds,
which can be used as natural tracers helpful in elucidating and quantifying subglacial hydrological processes,
subglacial bio/geochemical processes may also play an important role in global geochemical cycles, like the
global carbon cycle, or the cycling of iron and fertilization of the oceans.
Here we present the first geochemical measurements of the geochemical composition of basal water and pore
water from beneath the West Antarctic Ice Sheet. Our results point towards an oxygen depleted environment in the
Upstream C area (Kamb Ice Stream). Geochemical water and sediment also indicate the removal of inorganic
carbon potentially constituting a significant flux and release of inorganic carbon across the ice sheet grounding
zone into the sub ice shelf cavity.
Our results also point out that subglacial environments are far from being understood and that sample recovery
and insitu observations will be crucial for understanding subglacial environments and their role for ice sheet
dynamic, the interaction between ice sheets, the underlying lithosphere and the oceans as well as the impact of
subglacial processes on global geochemical cycles.
DE: 0726 Ice sheets
DE: 0790 Weathering (1625, 1886)
DE: 0793 Biogeochemistry (0412, 0414, 1615, 4805, 4912)
DE: 1615 Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912)
DE: 9310 Antarctica (4207)
SC: Cryosphere [C]
MN: 2007 Fall Meeting