Two-dimensional interpretation of gravity anomalies over sedimentary basins with an exponential decrease of density contrast with depth

The decrease of density contrast with depth in sedimentary basins is approx imated by an exponential function. The anomaly equation, in frequency domai n, of a prismatic model with an exponential density function is derived. Th e method has been extended to derive the Fourier transforms of the gravity anomalies of the sedimentary basin, wherein the basin is viewed as vertical prisms placed in juxtaposition. The gravity anomalies of the sedimentary;b asin are obtained by taking the inverse Fourier transforms. Filon's method has been extended for calculating accurate inverse Fourier transforms. The accuracy of the method has been tested using a synthetic example. A combina tion of space and frequency domain methods have been developed for inversio n of gravity anomalies over the sedimentary basin. The method has been appl ied to interpret one synthetic profile and one field profile over the Godav ari basin. The method developed in this paper to calculate the inverse Four ier transforms yields continuous spectrum with accurate values. The maximum depth deduced from the gravity anomalies is of the same order as the depth encountered to the basement at the Aswaraopeta borewell.