Paleogeodynamics of the Bransfield Strait

Abstract

The axes of zones split off between the northern continental slope of the Bransfield Basin and its southern slope belonging to the Antarctic Peninsula are reconstructed by determining the Euler poles and rotation angles that describe the splitting-off process. The revealed difference in the depths of joined isobaths of up to a hundred of meters reflects the different-scale slippage of peripheral parts of the continental crust from the main body of the Antarctic Peninsula along the plane of the through-lithosphere fracture. On the basis of paleogeodynamic reconstruction, it is possible to reconstruct also the initial bottom topography before the splitting off of the slipping fragments. It is shown that peripheral areas towered initially over the main surface of the shelf of the Antarctic Peninsula for many tens of meters. The locations of tectonic distortions along both borders of the strait due to transtension are reconstructed.