Geoelectrical deep soundings in Southern Africa using the Cabora Bassa power line

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E.K. Blohm
P. Worzyk
H. Scriba


Geoelectrical deep soundings with electrode spacings between 30 and 1250 km have been carried out from 1973 to 1975 in southern Africa using the Cabora Bassa power line. At several sounding stations (Schlumberger and bipole-dipole arrays) the electric potential differences have been recorded in different directions. For short current-electrode spacings (< 200 km) the direction of the electric field is nearly perpendicular to the direction between the current electrodes whereas it becomes more or less parallel for large electrode spacings (> 400 km). A possible cause for this rotation of the field may be a dyke system observed in the granitic crust.

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Blohm, E., Worzyk, P., & Scriba, H. (1977). Geoelectrical deep soundings in Southern Africa using the Cabora Bassa power line. Journal of Geophysics, 43(1), 665-679. Retrieved from


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