Structural lineaments from the magnetic anomaly maps of the eastern continental margin of India (ECMI) and NW Bengal Fan

Abstract

Three major structural lineaments are inferred from the magnetic and bathymetry data collected over the eastern continental margin of India (ECM) and NW Bengal Fan, covering the area between 10 degrees 55'N to 20 degrees 15'N and 80 degrees E to 88 degrees E. Analysis of magnetic data associated with these trends suggests that (1) trend1, located at the foot of the continental slope (around 3000 m water depth) represents the ocean-continent boundary (OCB) of ECMI, (2) trend 2 represents the northern extension of 85 degrees E ridge, abutting the continental shelf off Chilka Lake and (3) trend 3, locted over the continental shelf/slope between Visakhapatnm and Paradip represents a folded (ridges and depressions) nature of the continental basement. The study also reveals the occurrence of dyke intrusions within the continental crust landward of OCB, which might be related to the rift-phase volcanism along the ECMI