Elizabeth Demyanick, Geological Sciences, The Ohio State University, 125 South Oval Mall, 275 Mendenhall Laboratory, Columbus, OH 43202 and Terry Wilson, Ohio State University.
Extensional forces within the Antarctic Plate have produced the Transantarctic Mountains rift-flank uplift along the West Antarctic rift margin. This study employed the Antarctic Digital Database digital elevation model to obtain slope steepness and aspect maps of the Transantarctic Mountains (TAM) between the Royal Society Range and the Churchill Mountains, allowing definition of the position and orientation of the morphological axis of the rift-flank. The TAM axis, interpreted as a fault-controlled escarpment formed by coast-parallel retreat, provides a marker for the orientation of the faulted boundary between the TAM and the rift system. Changes in position and orientation of the TAM axis suggests the rift flank is segmented into tectonic blocks bounded by relay ramps and transverse accommodation zones. The transverse boundaries coincide with major outlet glaciers, supporting interpretation of rift structures between them. The pronounced change across Byrd Glacier points to control by structures inherited from the Ross orogen.
[Manuscript]
