Annals of Glaciology 41 2005 Bedrock topography and wind erosion sites in East Antarctica: observations from the 2002 US-ITASE traverse

ABSTRACT. Ice stratigraphy from deep-penetrating radar data collected during the 2002 US International Trans-Antarctic Scientific Expedition (US-ITASE) traverse shows evidence of a significant erosion surface and drift-filled basin related to a previously undiscovered 1400 m subglacial mountain betw...

Full description

Bibliographic Details
Main Authors: Brian C. Welch, Robert W. Jacobel
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.366.6545
http://www.stolaf.edu/other/cegsic/publications/Annals_41/AnnalsGlac--Welch_Jacobel_2005_EAIS_wind_scour_v41_p92.pdf
Description
Summary:ABSTRACT. Ice stratigraphy from deep-penetrating radar data collected during the 2002 US International Trans-Antarctic Scientific Expedition (US-ITASE) traverse shows evidence of a significant erosion surface and drift-filled basin related to a previously undiscovered 1400 m subglacial mountain between Hercules Dome (87842 0 S, 1088 W) and South Pole. The 3 MHz radar profile crosses three subglacial mountains at approximately 458 to the ice-flow direction. Cross-cutting reflectors in the top 500 m of ice stratigraphy are interpreted as angular unconformities resulting from wind erosion as the ice deforms over the mountain tops. The unconformities correlate locally with zones of high RADARSAT reflectivity. Several nearby sites with similar relatively high RADARSAT reflectivity adjacent to the traverse indicate that active wind erosion may be taking place at these locations as well. Based on the local correlation between surface wind scour and subglacial topography, we interpret the nearby cluster of bright RADARSAT reflectivity to indicate the presence of a small range of subglacial mountains. The ability to trace isochronal stratigraphy, associated with scour sites using shallow and deep radar, to nearby dated ice cores presents the possibility of exploiting wind-scour zones to access well-dated older ice with shallow-coring equipment.