The existing methods of determining the parameters of geological objects by gravity anomalies are associated with the approximation of the original data by analytical expressions, the parameters of which are subject to determination.
This paper provides the justification of the method of approximation of analytical expressions of geophysical fields by rational fractions and some other expressions. The method is based on the use of mathematical programming, mainly linear programming. The paper summarizes the experience of interpretation by this method of magnetic and gravitational anomalies on a computing machine “Ural-2”, which can operate in floating point mode ...
There are many ways of quantitative geologic interpretation of gravitational and magnetic fields. Let us consider the methods of selection that can be used to determine the elements of occurrence of geologic objects that create complex gravity and magnetic anomalies. In these methods, the curve obtained by field measurements is compared with the curves, which for bodies of correct geometric shape are calculated by appropriate formulas. In the case of irregularly shaped bodies, such curves have to be found using special palettes. Finally, modeling devices can be used for this purpose.
In the geologic interpretation of geophysical observations, it is often necessary to calculate the potential function in the lower half-plane from its values determined by measurements at the ground surface. This problem was solved by many researchers G. Renbow, for example, realized analytical continuation to the lower half-plane of the second derivative of the gravitational potential, with the help of which he determined the interface between two media of different densities.
Usually used in direct current electrical prospecting, the approximate method of taking into account the influence of the earth's surface consists in doubling the values of the electric potential found for the case of a body in an electric field in an unrestricted host medium, i.e., in the absence of an earth-air interface.In the present paper we analyze the errors introduced by the above method of taking into account the influence of the flat earth surface for bodies of regular geometric shape. For this purpose, for the approximate potential curves calculated using the usual doubling technique, such a shape of the body surface is selected for which the solution obtained by doubling is absolutely accurate.