Open AccessA method of physical approximation of the electromagnetic field
Author(s) -
Frenkel Michael A.,
Katsevich Alexander I.
Publication year - 1992
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1992.tb02083.x
Subject(s) - discretization , electromagnetic field , field (mathematics) , mathematical analysis , surface (topology) , grid , mathematics , continuation , geometry , physics , computer science , quantum mechanics , pure mathematics , programming language
SUMMARY Consideration is given to the accuracy of various linear transformations (LT) of a two‐dimensional transient electromagnetic (EM) field, measured on a certain discrete net of points on the Earth's surface (or water area) and contaminated by random noise of a known level. The medium is horizontally layered, except for one or several local domains within which the conductivity can be arbitrary. The normal section, the approximate location of the top of the inhomogeneity nearest to the observation surface, and the discretization intervals in space and time are assumed to be known. Expressions are derived for estimating the accuracy of calculation of arbitrary LT of the EM field: approximation, analytical continuation, calculation of field component derivatives, etc. These expressions can also be used to optimize field recording grid patterns in a stage of geophysical experiment planning. A method has been outlined for calculating arbitrary LT of the field both in the frequency ( w ) and in the time ( t ) domains. The results of testing this method, as well as the calculated estimates of accuracy for various LT of the field for the theoretical and model examples are presented.