Thursday, 30 August 2007 - 1:50 PM
4.P1.B-2
Neotectonic and other features of the Victoria Land Basin, Antarctica, interpreted from multibeam bathymetry data
Lawrence A. Lawver1, Marcy B. Davis1, Terry J. Wilson2, and Shipboard Scientific Party1. (1) Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, 10100 Burnet Rd. - R2200, Austin, TX 78758-4445, (2) School of Earth Sciences, Ohio State University, 125 S. Oval Mall, Columbus, OH 43210-1522
NBP0401 surveyed the Terror Rift and southern half of the Victoria Land Basin (VLB). Approximately 3000 km2 of continuous multibeam bathymetry were collected in McMurdo Sound between 77?S and 77?40'S and from 164?40'W to Ross Island. Additional coverage was collected in the VLB, north of Franklin Island and in a 15 by 40 km area near 76?N, 176?E. The data revealed numerous features indicative of significant neotectonism. Northwest of Franklin Island is a distributed field of pockmarks, up to 500 m in diameter and 30 m deep. West of Franklin Island, are eight nearly circular features up to 4 km in diameter and 100+ m high. Their circular shapes suggest a magmatic origin but without a magnetic signature, they may in fact be glacial in origin. The new bathymetric data, although limited, show that there are still many seafloor features in the western Ross Sea to be found.