Open AccessModel formulation and model smoothing for 2‐D magnetotelluric inversion
Author(s) -
Zhang A. J.,
Hobbs B. A.
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.tb04632.x
Subject(s) - magnetotellurics , inversion (geology) , smoothing , geophysics , algorithm , geology , finite difference , mathematics , electrical resistivity and conductivity , mathematical analysis , physics , seismology , statistics , quantum mechanics , tectonics
SUMMARY The finite‐difference method for solving electromagnetic induction equations numerically may be applied to 2‐D models composed of blocks of uniform resistivities. Inversion schemes based on such methods may require complex models composed of a large number of blocks in order to satisfy observational data. In such cases the resulting models are commonly found to be physically unacceptable—with the resistivity of isolated regions differing substantially from that of their surroundings. This paper illustrates the phenomenon and suggests an algorithm for deriving an) acceptable model. The algorithm achieves a smooth version of the inverted model with little sacrifice in data misfit and requires only a few extra inversion iterations.