INVERSION OF HETEROGENEOUS ANISOTROPIC MAGNETOTELLURIC RESPONSES
V.V. Plotkin
A.A. Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia
Keywords: Electrical anisotropy, synchronous 2D array MT data, lateral heterogeneity, effective conductivity tensor
Pages: 829-836
Abstract
Inversion of laterally heterogeneous MT responses collected by a dense synchronous 2D array allows a new approach to estimating electrical anisotropy. The procedure includes solving an overdetermined equation system, assuming distant-dependent anisotropy in a smooth approximation. Inversion is performed using an effective conductivity tensor, which approximates some limited domain of the survey polygon. The algorithm for simulating 2D array MT responses with the effective conductivity tensor approach implies correlation of surface components of the EM field measured simultaneously at all stations within the chosen domain of the survey polygon. The suggested technique of data acquisition and processing ensures reconstruction of the full conductivity tensor from laterally variable components of the EM field.
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