Pilot shallow drilling on the continental shelf, Dronning Maud Land, Antarctica

A light, mining drill rig deployed from the stern of a research vessel has been used to carry out shallow drilling in 212 m water depth on the contine ntal shelf in the eastern Weddell Sea. Penetration was 15 m below the seabe d with 18% recovery in the 31 hours available for the experiment. The recov ered glacigenic sediments are predominantly volcanic material of basaltic a nd andesitic composition with petrological characteristics and age similar to the continental flood basalts exposed in Vestfjella, about 130 km upstre am from the drill site. The sediments include a reworked marine Miocene dia tom flora. The material documents oscillations of the East Antarctic Ice Sh eet over the past 30 ka. The lowermost diamicton probably represents a defo rmation till, and the grounding line retreated past the drill site 30 km fr om the shelf edge about 30 kyr BP. A readvance occurred during the Late Wis consin Glacial Maximum. Assuming a reservoir correction of 1300 yr, marine conditions existed at the site between 10.1-7 kyr BP, and later at least be tween 2.8 and 2.5 kyr BP. The stratigraphy at the site has been disturbed b y iceberg ploughing and/or contact between the ice shelf and the sea floor during local advances after 2.5 kyr BP.