Structure and tectonics of the southwestern continental margin of India

Abstract

A NNW-SSE-trending graben in the inner shelf (40-60 m isobaths), a mid-shelf basement ridge (60-150 m isobaths), a shelf-margin basin (150-1000 m isobaths) and the Prathap Ridge Complex in the slope (1000-2000 m isobaths) extend as linear features along the southwestern continental margin of India between 12 degrees 20'N and 15 degrees 00'N. The basic structural framework of the margin seems to be influenced by the pre-existing Precambrian structural fabric of the continent. The mid-shelf basement ridge and the Prathap Ridge Complex are interpreted as manifestation of the rift-phase volcanism when India separated from Madagascar aound 84 Ma