Mantle Viscosity and Ice-Age Ice Sheet Topography

Ice-age paleotopography and mantle viscosity can both be inferred from observations of Earth's response to the most recent deglaciation event of the current ice age. This procedure requires iterative application of a theoretical model of the global process of glacial isostatic adjustment. Resul...

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Bibliographic Details
Published in:Science
Main Author: Peltier, W. Richard
Format: Article in Journal/Newspaper
Language:English
Published: American Association for the Advancement of Science (AAAS) 1996
Subjects:
Online Access:http://dx.doi.org/10.1126/science.273.5280.1359
https://www.science.org/doi/pdf/10.1126/science.273.5280.1359
Description
Summary:Ice-age paleotopography and mantle viscosity can both be inferred from observations of Earth's response to the most recent deglaciation event of the current ice age. This procedure requires iterative application of a theoretical model of the global process of glacial isostatic adjustment. Results demonstrate that the iterative inversion procedure converges to a paleotopography that is extremely close to that from the ICE-4G model. The accompanying mantle viscosity profile is furthermore shown to reconcile the requirements of aspherical geoid anomalies related to the mantle convection process, thus resolving a fundamental issue concerning mantle rheology. The combined model also explains postglacial sea level histories for the east coast of the United States.