The sourcewise approximation method is based on approximation of natural electromagnetic field by correspondent forward magntotelluric problem solution defined for model of conductive half-space with the elementary excess conductivity volume included in it. Approximation coefficient evaluated for each locations of elementary volume may be considered as function with respect to elementary volume location and allows to make decisions about non-homogeneous insertions of geological medium. In this paper, the possibility of sourcewise approximation method applying for interpretation of magnetotelluric sounding data is considered. It is shown that results of the sourcewise approximation of magnetotelluric data have a geometric sense and allow to determine the initial approximations for inverse problems solving, and, thus, help to reduce dimension of their solutions. MTSourceApprox software developed at the Research Station of RAS in Bishkek city is also briefly described in the paper. The aim of this software is sourcewise approximation of profile magnetotelluric data.

Zabinyakova Olga Borisovna, junior researcher, acting academic secretary; Research Station of Russian Academy of Sciences. 720049, Kyrgyzstan, Bishkek-49, Research Station RAS. E-mail: perah.92@inbox.ru.

Alexandrov Paul Nikolaevich, doctor of physics and mathematics, leading scientific researcher; Geoelectromagnetic Research Center of Institute of the Physics of the Earth of Russian Academy of Sciences. GEMRC IPE RAS, P.O.B. 30, 108840, Moscow, Troitsk, Russian Federation. E-mail: alexandr@igemi.troitsk.ru.

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