Extremely low long‐term erosion rates around the Gamburtsev Mountains in interior East Antarctica

The high elevation and rugged relief (>3 km) of the Gamburtsev Subglacial Mountains (GSM) have long been considered enigmatic. Orogenesis normally occurs near plate boundaries, not cratonic interiors, and large‐scale tectonic activity last occurred in East Antarctica during the Pan‐African (480–6...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Cox, S. E., Thomson, S. N., Reiners, P. W., Hemming, S. R., van de Flierdt, T.
Format: Article in Journal/Newspaper
Language:English
Published: American Geophysical Union 2010
Subjects:
Online Access:https://authors.library.caltech.edu/21429/
https://authors.library.caltech.edu/21429/1/Cox2010p12239Geophys_Res_Lett.pdf
https://authors.library.caltech.edu/21429/2/2010gl045106-ts01.pdf
https://authors.library.caltech.edu/21429/3/2010gl045106-ts02.pdf
https://authors.library.caltech.edu/21429/4/2010gl045106-txts01.pdf
https://authors.library.caltech.edu/21429/5/2010gl045106-txts02.pdf
https://resolver.caltech.edu/CaltechAUTHORS:20101220-100635447
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Summary:The high elevation and rugged relief (>3 km) of the Gamburtsev Subglacial Mountains (GSM) have long been considered enigmatic. Orogenesis normally occurs near plate boundaries, not cratonic interiors, and large‐scale tectonic activity last occurred in East Antarctica during the Pan‐African (480–600 Ma). We sampled detrital apatite from Eocene sands in Prydz Bay at the terminus of the Lambert Graben, which drained a large pre‐glacial basin including the northern Gamburtsev Mountains. Apatite fission‐track and (U‐Th)/He cooling ages constrain bedrock erosion rates throughout the catchment. We double‐dated apatites to resolve individual cooling histories. Erosion was very slow, averaging 0.01–0.02 km/Myr for >250 Myr, supporting the preservation of high elevation in interior East Antarctica since at least the cessation of Permian rifting. Long‐term topographic preservation lends credence to postulated high‐elevation mountain ice caps in East Antarctica since at least the Cretaceous and to the idea that cold‐based glaciation can preserve tectonically inactive topography.