Structures in rift-basin sediments on the conjugate margins of western Tasmania, south Tasman Rise, and Ross Sea, Antarctica

Abstract

Complex structures in sediments suggesting extensive wrench faulting have been observed on seismic records from the northern part of the Ross Sea, from the rift basin off West Tasmania and the rift basins of the South Tasman Rise. Wrench faulting affected rift-fill and transgressive strata in these areas up to the Eocene when deformation came to a halt. The end of wrench deformation is equated with the final separation of the Australian and Antarctic Plates and the establishment of open marine conditions. -Authors