Extremely low longâ€term erosion rates around the Gamburtsev Mountains in interior East Antarctica

• 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: unknown
• Published: American Geophysical Union 2010
• Subjects: thermochronology; East Antarctica; Gamburtsev Mountains; erosion rates; Prydz Bay; Lambert Graben; 1140 Geochronology: Thermochronology; 9310 Geographic Location: Antarctica (4207); 1051 Geochemistry: Sedimentary geochemistry; 1040 Geochemistry: Radiogenic isotope geochemistry; Antarctic; Gamburtsev Subglacial Mountains; Antarc*; Antarctica
• Online Access: https://doi.org/10.1029/2010GL045106

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 largeâ€scale tectonic activity last occurred in East Antarctica during the Panâ€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 preâ€glacial basin including the northern Gamburtsev Mountains. Apatite fissionâ€track and (Uâ€Th)/He cooling ages constrain bedrock erosion rates throughout the catchment. We doubleâ€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. Longâ€term topographic preservation lends credence to postulated highâ€elevation mountain ice caps in East Antarctica since at least the Cretaceous and to the idea that coldâ€based glaciation can preserve tectonically inactive topography. © 2010 American Geophysical Union. Received 12 August 2010; revised 30 September 2010; accepted 4 October 2010; published 20 November 2010. This work was supported by NSF-ANT0538580 and -ANT0817163. This work also benefited from discussions with the Earth System Evolution Program of the Canadian Institute for Advanced Research. Analytical assistance from Stefan Nicolescu is appreciated. We thank Stefanic Brachfeld, George Gehrels, Steve Goldstein, and Tom Wagner for samples and discussion. We acknowledge the FSU Antarctic Research Facility and the IODP for core samples. We thank John J. Veevers for extensive review comments. Published - Cox2010p12239Geophys_Res_Lett.pdf Supplemental Material - 2010gl045106-ts01.pdf Supplemental Material - 2010gl045106-ts02.pdf Supplemental Material - 2010gl045106-txts01.pdf Supplemental Material - 2010gl045106-txts02.pdf