GEOPHYSICAL RESEARCH2018, vol. 19, no. 4, pp. 16-30. https://doi.org/10.21455/gr2018.4-2

UDC 550.83.016

Abstract  References   Full text (in Russian)

SOURCEWISE APPROXIMATION OF GEOPOTENTIAL FIELDS. FROM THEORY TO PRACTICE

A.V. Pugin

Mining Institute, Ural Branch of Russian Academy of Sciences, Perm, Russia

Abstract. Theoretical definitions contain idealizations and by that differ from practical ones. Various algorithms of sourcewise approximation produce different distributions of equivalent sources. They all are theoretically equivalent but practically result to odds in mathematical transformations of geopotential fields. The article shows a practical definition has finite bounds of an integration domain whilst a theoretical one has no limits. This leads to the fact: different approximations have diverse complete surface integrals of field which is not possible the same as for real anomalous sources. The problem has no general solution but cannot be ignored. Interpreter could choose most useful algorithm to solve the geological problem if he has a number of them. The approximation algorithm has distinct advantages if it is able to analyze the structure of input data. This increases its chance to be selected for applying.

Keywords: sourcewise approximation, geopotential field, problem definition, algorithm, equivalent source, transformation.

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