NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Late Pleistocene and Holocene Glacial Evolution and Isotasy in the Antarctic PeninsulaEmploying a numerical model of Payne et al. that simulates the late-Pleistocene evolution of the former Antarctic Peninsula Ice Sheet (APIS) as a basis, we compute the present-day postglacial vertical isostasy of this region. The region may also experience significant mid-to late-Holocene glacial mass changes. Climate and oceanographic studies indicate that the ice mass imbalance of this region may be of larger magnitude that elsewhere in Antarctica. We compute the crustal response to these more recent ice mass changes and Holocene fluctuations with a simple gravitating Earth model consisting of an elastic lithosphere and a viscoelastic mantle (half-space). The calculations demonstrate that the present-day response could be significant, possibly at the level of about 4 - 11 mm/yr. Such significant crustal motion could be driven by glacial mass changes integrated over the last 1000 years if the regional mantle viscosity is below about 2 x 10(exp 20) Pa sec. In this lower viscosity range, present-day crustal motion has a significant phase-lagged character and the composite lithosphere/mantle viscoelastic response to late-Holocene events dominates over purely elastic (instantaneous) responses to present-day ice mass changes. For a higher mantle viscosity, greater than about 5 x 10(exp 20) Pa sec, the predicted present-day vertical isostasy is dominated by gravitational response to glacial unloading during the 18 - 6 kyr BP collapse of the APIS, and is analogous to that known to be occurring in the Gulf of Bothnia and Hudson Bay.
Document ID
20000080175
Acquisition Source
Jet Propulsion Laboratory
Document Type
Other
Authors
Ivins, E. R.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
Raymond, Carol A.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
Heflin, M. B.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
James, T. S.
(Geological Survey of Canada Sidney, British Columbia Canada)
Date Acquired
August 19, 2013
Publication Date
January 1, 1989
Subject Category
Geophysics
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Available Downloads

There are no available downloads for this record.
No Preview Available