Special geophysical studies for boreholes drilling for oil and gas

Considered are general principles of special geophysical investigations conducted in the limited number of wells according to the special program to solve the following geological tasks for all the oil field: determination of water-oil surface, gas-water surface, and gas-oil surface, establishment of the collector criteria, estimation of the potential yield for various reservoir types and various capacities of complex type reservoirs etc. Incidentially methods of repeated radioactivity logging (in different modifications), tracer techniques and others are used, which permits to study dynamic processes in a stratum. Classification scheme of special geophysical investigations, based on technological principle is presented