The types and geophysical characteristics of terrigenous rock reservoirs of Dneprovsko-Donetskaya basin

The types and geophysical characteristics are described of terrigene reservoir rocks in the Dnieper-Donets hollow, singled out by a combination of borehole mining-geophysical investigations (electrical logging, gamma-ray logging, neutron-gamma logging, acoustic logging). It has been established that due to the existence of a penetration band neutron-gamma logging readings are not affected by gas and are characteristic of sand reservoirs. Typical for the granular reservoir rocks are increased or anomalously high natural gamma-ray activities. It has been found that the high gamma-ray activity is accounted for by the presence in the reservoir rocks of accessory and rare earth minerals affecting the readings of gamma-ray logging rather than by an increased clayiness