We offer technology of reservoir identification and saturation nature estimation within the oil-and-gas producing wells by spectrometry neutron gamma-ray logging (SNGK) and spectrometry natural gamma-ray logging (SGK)-methods.

Description

Problems to be solved

• lithology dismembering of a geological section based on studying of the neutron and gamma-ray properties and radioactive element contents (H, Cl, B, Fe, Ca, Si, etc.) and their relations;
• reservoir identification and porosity coefficient determination;
• oil-saturation coefficient determination;
• clay mineral composition determination;
• identification of the polymictic sandstones with high content of potassic fieldspar, and monazite sandstones with high content of thorium within the high-radioactive reservoir sections;
• identification of a fractured reservoir as well as zones of the limestone secondary dolomitization by an increased content of uranium;
• identification of the watered intervals by geochemical anomalies induced by radium accumulation on the cement stone due to travelling of the first-line front of injected brine water within an oil-bearing formation.   

This technology is carried out by a complex digital apparatus of spectrometry radioactive logging (SNGK-K) that provides wide-range spectrometry of neutron gamma-ray logging (SNGK) as well as spectrometry of GR-S natural gamma-ray that was developed by JSC VNIIGIS jointed with JSC GITAS. Standard diameter of the SNGK-Sh-2 downhole tools (90 mm) and small diameter of the SNGK-Sh (48 mm) allows to use them for through-tubing well surveying.

Features

• improved information capacity due to application of wide-range SNGK modification in a dual-sonde version;
• it is possible to carry out multi-method measurements by one trip.

PAO NPP VNIIGIS and AO NPF GITAS supply tools and service in geological problems solving by the offered technology.

Results

Technology of reservoir identification and saturation nature estimation within the oil-and-gas producing wells by SNGK- and SGK-methods