Integrated G3 Investigations in Antarctica

Abstract

CSIR-NGRI has been carrying out integrated G3 investigations in Antarctica since the second IAE. The geophysical studies of the initial 25 years of IAE included surface and helicopter-borne magnetic, EM, seismic, gravity, and paleomagnetic surveys. A total of 60 line-km magnetic profiles over the ice-shelf revealed the magnetic characteristics of the bedrock beneath the ice cover. Based on these and in conjunction with the early seismic studies, a crustal structural model was evolved. Secondary sulfide mineralisation near a suspected fissure zone in Schirmacher Oasis (SO) was inferred. It was based on the multi-frequency EM and radiometric measurements. The helicopter-borne magnetic N-S profiles over an area of 100x100sq.km with a spacing of about 3.0 km between SO and Wohlthat Mountains (WM) yielded gross features of sub-glacial topography nunataks (exposed peaks of sub-glacial hills).