Tectonic fabric of the Atlantic and Indian oceans and continental drift

Abstract

The floor of the Indian Ocean is dominated by (1) the seismically active Mid-Oceanic Ridge, (2) scattered linear micro-continents (mostly meridional), and (3) fracture zones (some displace the axis of the Mid-Oceanic Ridge and others parallel the micro-continents). The pattern suggests that movement along the Diamantina Fracture Zone has displaced Australia to the east relative to Broken Ridge. In the Arabian Sea north-northeast trending fracture zones have displaced the axis of the Carlsberg Ridge. The complex tectonic fabric of the Indian Ocean is difficult to explain in terms of a simple pattern of convection currents. The location and origin of the Mid-Oceanic Ridge, of oceanic rises, aseismic ridges and transcurrent fault systems must be accounted for in any hypothesis of continental displacement despite unique or exotic assumptions as to strength, viscosity or composition of the oceanic crust and mantle.