ALBERT

Description: The Antarctic geomagnetics' community remains very active in crustal anomaly mapping. More than 1.5 million line-km of new air- and shipborne data have been acquired over the past decade by the international community in Antarctica. These new data together with surveys that previously were not in the public domain significantly upgrade the ADMAP compilation. Aeromagnetic flights over East Antarctica have been concentrated in the TransantarcticMountains, the Prince CharlesMountains – Lambert Glacier area, and western Dronning Maud Land (DML)—Coats Land. Additionally, surveys were conducted over Lake Vostok and the western part of Marie Byrd Land by the US Support Office for Aerogeophysical Research projects and over theAmundsen Sea Embayment during the austral summer of 2004/2005 by a collaborative US/UK aerogeophysical campaign. New aeromagnetic data over the Gamburtsev Subglacial Mountains (120,000 line-km), acquired within the IPY Antarctica's Gamburtsev Province project reveal fundamental geologic features beneath the East Antarctic Ice sheet critical to understanding Precambrian continental growth processes. Roughly 100,000 line-km of magnetic data obtained within the International Collaboration for Exploration of the Cryosphere through Aerogeophysical Profiling promises to shed light on subglacial lithology and identify crustal boundaries for the central Antarctic Plate. Since the 1996/97 season, the Alfred Wegener Institute has collected 90,000 km of aeromagnetic data along a 1200 km long segment of the East Antarctic coast over western DML. Recent cruises by Australian, German, Japanese, Russian, British, and American researchers have contributed to long-standing studies of the Antarctic continental margin. Along the continental margin of East Antarcticawest ofMaud Rise to the George V Coast of Victoria Land, the Russian Polar Marine Geological Research Expedition and Geoscience Australia obtained 80,000 and 20,000 line-km, respectively, of integrated seismic, gravity and magnetic data. Additionally, US expeditions collected 128,000 line-km of shipborne magnetic data in the Ross Sea sector.