GENERAL GEOLOGY

Detailed explanation-1: -Spectral gamma ray logs are most useful in identifying the following: Clay minerals. Illite clays are rich in potassium, whereas smectite and kaolinite contain thorium. The thorium to potassium ratio can distinguish illitic from smectitic shales and so provide a correlation tool.

Detailed explanation-2: -Gamma ray logging is a method of measuring naturally occurring gamma radiation to characterize the rock or sediment in a borehole or drill hole. It is a wireline logging method used in mining, mineral exploration, water-well drilling, for formation evaluation in oil and gas well drilling and for other related purposes.

Detailed explanation-3: -Gamma ray logs are used primarily to distinguish clean, potentially productive intervals from probable unproductive shale intervals. The measurement is used to locate shale beds and quantify shale volume. Clay minerals are formed from the decomposition of igneous rock.

Detailed explanation-4: -Gamma-ray logs have two fundamental benefits that make them important to studies of geological materials: (1) they provide a basic analysis of grain size and, (2) they can be collected in any form of cased borehole, above or below water.