APPROXIMATE 3D ESTIMATION OF GRAVITY ANOMALIES, CAUSED BY THE SPHERICAL SHAPE OF THE EARTH
The article presents a method for approximate estimation of differences in gravity anomalies caused by the use of “flat” and “spherical” models of the Earth during interpretation of gravimetric survey materials within large areas. As a lower estimate of the influence of the Earth surface shape, it is proposed to use the difference of the radial and vertical derivatives of the gravitational potential. The method is based on the source-like approximation of discrete values of the anomalous gravitational field; is characterized by high accuracy of the results and does not require a priori information about perturbing objects. The method possibilities are demonstrated on model examples and materials of a medium-scale gravimetric survey of an O-40 sheet (Perm region). Also considered the cartographic aspects of geo-density modeling using the Gauss-Kruger system of plane rectangular coordinates.