DEEP GEOELECTRICAL STUDIES IN THE FINNMARK AND THE PECHENGA AREA BY MEANS OF THE KHIBINY SOURCE

As part of the Soviet-Norwegian programme in geology and geophysics, a n investigation of electroconductivity in the upper part of the Earth' s crust was carried out in 1989-1991. The measurements were performed using an electrical dipole source, 'Khibiny', which is situated on the Kola Peninsula, close to the Norwegian border. A 26 kW car generator supplied square pulses with a peak to peak current of 100 A in the 'Kh ibiny' cable; at a frequency of 0.125 Hz. The distance between the sou rce and the measuring points varied from 60 to 130 km. A stacking tech nique was applied to identify the weak electromagnetic signals. All th e measurements were conducted using a six-component digital automatic station, ZAIS, produced at the Institute of Fundamental Physics of the USSR Academy of Science. As a result of the studies, several conducti ve current channels in the Pechenga structure on the Russian side of t he border were traced into the Pasvik area in Norway. Detailed informa tion on the deeper parts of the electroconductive structures in this a rea was obtained.