Gravitational Modeling.

Formulas for computing the gravitational effect of some simple two-and three-dimensional geometric figures are presented in forms suitable for use with digital computers and in many cases, programmable desk calculators. Basic computation schemes are presented for complex two-and-three-dimensional bodies of arbitrary shape. Some simple inversion rules or techniques are presented which yield approximations of depth based on simple geometric figures. Such inversion techniques are particularly applicable where gravity measurements are sparse. These techniques yield first approximations of the depth, size and shape of the mass or masses causing a given residual gravity anomaly. Density or density contrast is independent of depth, size and shape and is discussed seperately. Density and porosity are defined by appropriate equations. Generalized density relationships based on rock types are discussed. Equations for the determination of effective densityity from gravity measurements are presented. The concluding remarks cover some general aspects of gravitational modeling. Author