Paper No. 99-12
Presentation Time: 11:10 AM
TO UNDERSTAND THE SUBGLACIAL GEOLOGY OF THE GAMBURTSEV SUBGLACIAL MOUNTAINS AND PRYDZ BAY REGIONS, EAST ANTARCTICA
In this presentation we provide our investigations of the subglacial geology in the Grove Mountains, Prydz Bay regions and the Windmill Islands, new surface wave observations: S-velocity model and Moho topography of the Antarctic Plate as well as bedrock drilling project to be conducted in the Gamburtsev Subglacial Mountains to improve our understanding of the subglacial geology of East Antarctica, especially the Gamburtsev Subglacial Mountains. We provided evidence of the occurrence of HP mafic granulites from the Grove Mountains for a collisional tectonic setting for the Prydz Belt, which supports the notion that East Gondwana was not finally assembled until the Cambrian. The earliest Cambrian orogenic belt can extend into the Gamburtsev Subglacial Mountains and overprinted the Archean-Proterozoic block with Paleo-Archean rocks up to 3.5 Ga nearby the Rauer Group and the Vestfold Hills, but didn’t overprint the inland areas of Wilkes Land. Our new surface wave observations: S-velocity model and Moho topography of the Antarctic Plate showed that East Antarctic has a thick crust and lithosphere like a stable craton in the other continents. The area close to the Gamburtsev Subglacial Mountains has the thickest crust(~60 km), which is not contradictory to a crust thickness formed around the end of Precambrian or earliest Cambrian, but the area with the thickest lithosphere (~150 km) located in the middle from Dome A to Dome C. The bedrock drilling project has been supported by NSFC and will be conducted in the future four to five years. The preliminary plan and international collaborations will be discussed.