Spectral analyses of offshore magnetic data for computing depths to the basement rocks

This paper deals with the computation of the depth to the magnetic interface from the total magnetic field intensity values obtained along profiles in the offshore area between Vengurla and Rajapur bay off the West Coast of India, by the application of one dimensional spectral analysis method.From the response characteristics of the total field magnetic values it is surmised that the magnetic interface may be identified with the Deccan trap series of rocks which are likely to form the magnetic basement rocks in this area.The plot of depths to the basement rocks as obtained from spectral analysis indicates that the basement is sloping towards outer edge of the Continental Shelf though not uniformly.