JOURNAL OF THE BALKAN GEOPHYSICAL SOCIETY, Vol. 1, No 1, February 1998, p. 3-13, 8 figs.

A smoothness constrained algorithm for the fast 2-D

inversion of DC resistivity and induced polarization data

P.I. Tsourlos*, J.E. Szymanski** and G.N. Tsokas*

*Geophysical Laboratory, Aristotelian University of Thessaloniki, 54006 Thessaloniki Greece.

**Department of Electronics, University of York, Heslington, York Y01 5DD, U.K.

( Received 10 January 1998; accepted 1 February 1998 )

Abstract: A fast smoothness constrained algorithm for the 2-D inversion of direct current and induced polarization data is presented. The procedure is fully automated and accelerated by the use of a Quasi-Newton update of the Jacobian matrix. The need for a fast algorithm is discussed and a detailed presentation of its features is given. The features of the algorithm are presented in detail and comparisons to other techniques are shown. The algorithm is also used to invert Induced Polarization (IP) data sets. Finally, tests of the algorithm with synthetic and real data are presented. The algorithm proves to be robust noise insensitive and produces good quality inversions. The tests with real data indicated that it could be a reliable tool for data interpretation.

Key Words: Resistivity Inversion, IP Inversion, Smoothness Constrained