Title Antarctica's continent-ocean transitions; consequences for tectonic reconstructions
Author Gohl, K.
Author Affil Gohl, K., Alfred Wegener Institute for Polar and Marine Research, Potsdam, Federal Republic of Germany. Other: Jet Propulsion Laboratory
Source Open-File Report - U. S. Geological Survey, No.OF2007-1047, p.29-38, ; 10th international symposium on Antarctic earth sciences; Antarctica; a keystone in a changing world, Santa Barbara, CA, Aug. 26- Sept. 1, 2007, edited by A. Cooper and C. Raymond. Publisher: U. S. Geological Survey, Reston, VA, United States. ISSN: 0196- 1497
Publication Date 2007
Notes In English. Accessed on May 27, 2010. 62 refs. Ant. Acc. No: 88362
Index Terms Antarctica; continental crust; continental margin; crust; geodynamics; Gondwana; International Polar Year 2007-08; IPY 2007-08 Education, Outreach and Communication Publications; kinematics; mapping; models; oceanic crust; paleogeography; passive margins; plate collision; plate tectonics; reconstruction; rifting; USGS
Abstract Antarctica was the centerpiece of the Gondwana supercontinent. About 13,900 km of Antarctica's 15,900-km-long continental margins (87 percent) are of rifted divergent type, 1600 km (10 percent) were converted from a subduction type to a passive margin after ridge-trench collision along the Pacific side of the Antarctic Peninsula, and 400 km (3 percent) are of active convergent type. In recent years the volume of geophysical data along the continental margin of Antarctica has increased substantially, which allows differentiation of the crustal characteristics of its continent-ocean boundaries and transitions (COB/COT). These data and geodynamic modeling indicate that the cause, style, and process of breakup and separation were quite different along the Antarctic margins. A circum-Antarctic map shows the crustal styles of the margins and the location and geophysical characteristics of the COT. The data indicate that only a quarter of the rifted margins are of volcanic type. About 70 percent of the rifted passive margins contain extended continental crust stretching between 50 and 300 km oceanward of the shelf edge. Definitions of the COT and an understanding of its process of formation has consequences for plate-kinematic reconstructions and geodynamic syntheses.
URL http://pubs.usgs.gov/of/2007/1047/
Publication Type conference paper or compendium article
Record ID 299611