Estimation of Ash Content in Coal from Geophysical Logs - A Case Study from Talcher Coal Field, Orissa

Anomalous response of borehole logging parameters like natural gamma, gamma-Gamma and neutron against 104 coal beds encountered in six boreholes in Talcher coal field, Orissa were studied. Corresponding ash content of the coal beds were also noted from band by band chemical analysis. A relationship thus has been established between the ash content of coal and the corresponding geophysical log response of natural gamma, neutron and gamma-Gamma parameters. A simple geophysical method has been established for determination of ash content of coal beds from geophysical logs in Talcher coal field area. Such methods can also be developed for different coal fields and Gondwana basins of the country paving the way for a much more economic and rapid non core drilling instead of the prevalent expensive core drilling for analysis of ash content of coal samples.