Informatics Publishing Limited

Kalpan Choudhury ¹, R. B. Singh ², Anwar Hakim ², S. K. Singh ²

Affiliations
1 Central Geophysics Division, Geological Survey of India, Kolkata - 700 016, IN
2 Geophysics Division, Geological Survey of India, Aliganj, Lucknow - 226 024, IN

Abstract

Integrated geophysical surveys comprising resistivity and chargeability (both gradient and Dipole-Dipole), SP, magnetic and borehole Mise-a-La-Masse methods coupled with geoelectrolysis techniques and geochemical analysis of soil samples led to the delineation of several auriferous sulphide bodies in the eastern Mahakoshal belt. Combined analysts of surface geophysical, borehole geophysical and geoelectrolysis methods are presented in respect of three areas viz. Gurahar Pahar, Tisihwa and Gulaldih Geophysical interpretations were based on the observed response (parametric survey) over the different exposed rock types in the area Moderately high chargeability coupled with moderate low resistivity, negative SP, high Geo-Electrochemical anomaly supported by geochemical soil sample anomaly proved to be indicative of concealed sulphide conductors. Mise-a-La-Masse technique delineated the extension of the sulphide body projected on a horizontal plane and its dip direction.

Keywords

Exploration Geophysics, Gold, Eastern Mahakoshal Belt, Uttar Pradesh, Madhya Pradesh.

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Kalpan Choudhury ¹

Affiliations
1 Central Geophysics Division, Geological Survey of India, Kolkata, IN

Abstract

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.

Keywords

Coal, Ash Content, Geophysical Log, Natural Gamma, Neutron, Gamma-Gamma, Talcher Coal Field, Orissa.

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