FOCUSED CURRENT MARINE GEOELECTRIC PROSPECTING METHOD

摘要

The invention relates to geophysical investigations, to marine geoelectric prospecting methods. The two variants of the inventive method consist in exciting an electromagnetic field in a studied medium thickness by transmitting two similar rectangular current pulses thereto, wherein one pulse is transmitted during a direct travelling of a sounding device along the investigated profile and the other pulse is transmitted during a back travelling thereof, in measuring the instantaneous value of first and second electric potential differences during the time between the current pulses, wherein, in order to exclude the axial current density component under a sounding site, the equal-zero conditions of the electric potential difference resultant along the profile is ensured, in calculating three sets of normalised electrical parameters on the base of difference values, in solving an inverse problem by means of an differential equation for the dipole source voltage in a electrochemically polarisable medium using said obtained parameters, in producing a stacked data according to said electrical parameters and in determining the conductivity of the medium elements, the induced-polarisation factor and the decay time constant of the induced polarisation potential difference.