A new method for the automatic interpretation of Schlumberger and Wenner sounding curves

A fast iterative method for the automatic interpretation of Schlumberger and Wenner sounding curves is based on obtaining interpreted depths and resistivities from shifted electrode spacings and adjusted apparent resistivities, respectively. The method is fully automatic. It does not require an initial guess of the number of layers, their thicknesses, or their resistivities; and it does not require extrapolation of incomplete sounding curves. The number of layers in the interpreted model equals the number of digitized points on the sounding curve. The resulting multilayer model is always well‐behaved with no thin layers of unusually high or unusually low resistivities. For noisy data, interpretation is done in two sets of iterations (two passes). Anomalous layers, created because of noise in the first pass, are eliminated in the second pass. Such layers are eliminated by considering the best‐fitting curve from the first pass to be a smoothed version of the observed curve and automatically reinterpreting i...

[1]  C. Pekeris.  Direct method of interpretation in resistivity prospecting , 1940 .

[2]  R. Maillet.  THE FUNDAMENTAL EQUATIONS OF ELECTRICAL PROSPECTING , 1947 .

[3]  K. Deppermann.  Die Abhängigkeit des scheinbaren Widerstandes vom Sondenabstand bei der Vierpunkt-Methode , 1954 .

[4]  L. Cagniard.  Abaque pour sondages électriques sur glace , 1959 .

[5]  L. Alfano.  INTRODUCTION TO THE INTERPRETATION OF RESISTIVITY MEASUREMENTS FOR COMPLICATED STRUCTURAL CONDITIONS , 1959 .

[6]  Ernesto Orellana.  Properties and drawing of the so-called Dar Zarrouk curves , 1963 .

[7]  G. Kunetz.  Principles of direct current resistivity prospecting , 1966 .

[8]  D. Ghosh.  THE APPLICATION OF LINEAR FILTER THEORY TO THE ' DIRECT INTERPRETATION OF GEOELECTRICAL RESISTIVITY SOUNDING MEASUREMENTS * , 1971 .

[9]  L. Muffler,et al.  Resistivity, self-potential, and induced-polarization surveys of a vapor-dominated geothermal system , 1973 .

[10]  W. Stanley,et al.  Preliminary interpretation of electrical sounding curves obtained across the Snake River Plain from Blackfoot to Arco, Idaho , 1973 .

[11]  D. J. O'Neill.  Improved linear filter coefficients for application in apparent resistivity computations , 1975 .

[12]  Walter L. Anderson,et al.  Improved digital filters for evaluating Fourier and Hankel transform integrals , 1975 .

[13]  O. Koefoed,et al.  Geosounding Principles: Resistivity Sounding Measurements , 1980 .

[14]  Adel A.R. Zohdy,et al.  Application of surface geophysics to ground-water investigations , 1980 .

[15]  E. Mundry.  The effect of a finite distance between potential electrodes on Schlumberger resistivity measurements—A simple correction graph , 1980 .