HR: 0800h
AN: C21A-0973    [Abstracts]
TI: Investigating the crustal elements of the central Antarctic Plate (ICECAP): How long-range aerogeophysics is critical to understanding the evolution of the East Antarctic ice sheet
AU: Blankenship, D D
EM: blank@ig.utexas.edu
AF: Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, 4412 Spicewood Springs Rd. #600, Austin, TX 78759-8500 United States
AU: Brozena, J M
AF: Naval Research Laboratory, Code 7421, 4555 Overlook Ave. SW, Washington, DC 20375-5350 United States
AU: Siegert, M J
AF: Bristol Glaciology Centre, School of Geographical Sciences, Tyndall Avenue, Bristol, BS8 1TH United Kingdom
AU: Morse, D L
AF: Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, 4412 Spicewood Springs Rd. #600, Austin, TX 78759-8500 United States
AU: Dalziel, I W
AF: Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, 4412 Spicewood Springs Rd. #600, Austin, TX 78759-8500 United States
AU: Lawver, L A
AF: Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, 4412 Spicewood Springs Rd. #600, Austin, TX 78759-8500 United States
AU: Holt, J W
AF: Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, 4412 Spicewood Springs Rd. #600, Austin, TX 78759-8500 United States
AU: * Childers, V A
EM: vicki.childers@nrl.navy.mil
AF: Naval Research Laboratory, Code 7421, 4555 Overlook Ave. SW, Washington, DC 20375-5350 United States
AU: Bamber, J L
AF: Bristol Glaciology Centre, School of Geographical Sciences, Tyndall Avenue, Bristol, BS8 1TH United Kingdom
AU: Payne, A J
AF: Bristol Glaciology Centre, School of Geographical Sciences, Tyndall Avenue, Bristol, BS8 1TH United Kingdom
AB: The highlands of the central Antarctic Plate have been the nursery for East Antarctic ice sheets since at least the early Oligocene separation of Antarctica and Australia. Significant strides have been made in deciphering the marine geological, geophysical, and geochemical record of the deposits left by these sheets and the Pleistocene paleoclimate record from ice cores taken from the central reaches of the contemporary ice sheet. Most recently, the scientific community has realized the importance of the isolated biome represented by the subglacial lakes that characterize the domes of the central East Antarctic ice sheet and evolve in concert with them. Understanding the evolution of the East Antarctic ice sheet and its sub-glacial environment would be a major contribution to the IPY 2007-2008 international effort. Critical to understanding offshore and ice core records of paleoclimate, as well as the distribution/isolation of any subglacial lake systems, is developing a comprehensive understanding of the crustal elements of the central Antarctic Plate. A complete understanding of the evolution of East Antarctic ice sheets throughout the Cenozoic requires knowledge of the boundaries, elevation and paleolatitude of these crustal elements through time as well as evidence of their morphological, sedimentological and tectono-thermal history. The basic impediments to gaining this understanding are the subcontinental scale of the central Antarctic Plate and the one to four kilometers of ice cover that inhibits direct access. It is possible however to provide a substantial framework for understanding these crustal elements through a comprehensive program of long-range airborne geophysical observations. We have proposed a plan to measure gravity, magnetics, ice-penetrating radar, and laser/radar altimetry over the Gamburtsev, Vostok and Belgica subglacial highlands beneath Domes A - C of the contemporary East Antarctic ice sheet using a Navy P-3 aircraft based in McMurdo. Such measurements would help characterize crustal boundaries, establish absolute bedrock elevation and contemporary basal melt distribution (for boundary conditions of ice sheet and lake evolution), and reveal detailed subglacial geomorphology. A P-3 aircraft based in McMurdo would provide access to more than half of the continent without the difficult logistic support of remote field camps and fuel caches.
DE: 8109 Continental tectonics--extensional (0905)
DE: 1824 Geomorphology (1625)
DE: 1863 Snow and ice (1827)
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting