Nearshore magnetic anomalies of inner shelf of Bhimunipatnam-Pudimadaka, east coast of India

Abstract

Analysis of marine magnetic data of the nearshore marine environment between Bhimunipatnam and Pudimadaka, on the East Coast of India indicate charnockite intrusions in the innershelf in certain areas. From the analysis of magnetic data, the causative sources (intrusive bodies) are estimated to occur at depths varying between 80 and 200 m from the sea surface. In the Lawson's Bay the high-amplitude anomaly is attributed to basement uplift due to folding in granitic or gneissic rocks. Even though heavy mineral concentrations coincide with magnetic anomaly at certain places, a distinct correlation between heavy mineral percentage of the surface sediments and magnetic data is not always discernible.