Premium
GEOLOGICAL INFORMATION FROM FLUCTUATING EARTH‐CURRENTS *
Author(s) -
HOOGERVORST G. H. T. C.
Publication year - 1979
Publication title -
geophysical prospecting
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.735
H-Index - 79
eISSN - 1365-2478
pISSN - 0016-8025
DOI - 10.1111/j.1365-2478.1979.tb00966.x
Subject(s) - equipotential , equipotential surface , contour line , geology , geophysics , potential field , magnetotellurics , potential gradient , noise (video) , field (mathematics) , geodesy , regional geology , electrical resistivity and conductivity , similarity (geometry) , simple (philosophy) , hydrogeology , geometry , mineralogy , physics , mathematics , metamorphic petrology , geotechnical engineering , meteorology , philosophy , epistemology , quantum mechanics , artificial intelligence , computer science , pure mathematics , image (mathematics)
A bstract Investigation of fluctuating earth‐currents has led to a simple method of eliminating the noise superimposed on the signal in geoelectrical resistivity surveys. The similarity of the potential fluctuations, simultaneously measured at different locations, is used to calculate the direction and magnitude of the potential gradient. Contour maps of equipotential lines were made, both from disjointed gradient measurements using a numerical approximation method and from a network of measured potential differences. These contour maps were compared with potential fields calculated for simple homogeneous models. A good fit was obtained with the field of a conducting plate. When this is subtracted from the measured field, the result is a map that shows anomalies that can be correlated with geological structures.