What is a Gamma Ray Correlation Log?
The Gamma Ray Correlation Tool/Log ensures tools test the zone of interest. A gamma-ray correlation log is a recording of the natural gamma radiation of the formation around the well bore and does not change with well treatment or production. It can be used to correlate the depths of the other well logs and the core gamma-ray log from the same hole, almost always run in conjunction with other well logs. The natural gamma-ray radiation emitted from rocks varies with the lithology. The radiation comes from the radioactive decay of Uranium, Thorium, and Potassium, present as trace elements. Shale is composed of more of these elements than a clean sandstone or limestone. Generally, the greater the shale content, the greater is the quantity of radiation.
