Seafloor morphology and acoustic facies of the George V Land shelf

• Published in: Deep-sea research. Part II, Topical studies in oceanography Vol. 50; no. 8; pp. 1343 - 1355
• Main Authors: Beaman, Robin J, Harris, Peter T
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-05-2003
• Subjects: Marine; PSE, Antarctica, George V Land
• ISSN: 0967-0645; 1879-0100
• DOI: 10.1016/S0967-0645(03)00071-7

To study the seafloor morphology on the George V Land shelf, East Antarctica, over 2000
km of high-frequency 3.5–27
kHz, echo-sounder data were collected between February and March 2000. The shelf can be divided into four acoustic facies: (a) Type IA-2 seabed is ice-keel turbate found on mid- to outer-shelf banks on seafloor less than 500
m deep; (b) Type IB seabed is siliceous mud and diatom ooze drift, drape and fill deposits within the George V Basin between 750 and 850
m depth; (c) Type IIB seabed is smooth diamicton below 500
m depth, and occasionally has low-relief megaflutes or ridge and swale features; (d) Type IIIC seabed is high relief ridges and canyons from the coast to the deepest part of the George V Basin. The acoustic facies are explained in terms of glacial and oceanographic influences on the shelf since the Last Glacial Maximum.