Continental-Oceanic transition– examples from the Indian ocean passive margins

Abstract

Several studies have been conducted since last 50 years to understand the crustal architecture of the passive margins. The conjugate passive margins along Indian Ocean are very less surveyed and studied due to geographical and political constraints. This study has been carried out by inspecting geophysical characteristics of selected conjugate margin segment (Africa-Antarctica, India-Antarctica) in order to understand the structure of ocean-continental transition and to locate the ocean continental boundary. The freely available information about the potential field data and published seismic profiles has been gathered and reconstructed for time of breakup for selected margin. The study reveals that Antarctica- Africa conjugates are magma rich passive margin. A wide oceanic continental transition is observed along Antarctica margin and narrow along the Africa margin. The detailed study along Antarctica- India suggests the conjugate pair is asymmetric. The Antarctica margin is wider than the Indian margin. However, the structure along conjugate pair is quite similar.