Device for geophysical reconnaissance of mineral deposits

摘要

A 3 electrode D.C. system is used, whereby a controlled direct current is injected into the ground at two points, the one being via a multi prong earthing device, at the surface, the other being by means of a bore-hole electrode penetrating the ground. The current is impressed for a predetermined duration, during which period the chemical reaction potential is measured and compared with a nominal value. The output controls the level of impressed current which is monitored and fed to a chart recorder. By this means a polarisation curve is constructed of voltage against current.