Multielectrode resistivity imaging technique for the study of coal seam

Abstract

The multielectrode resistivity imaging method has been used to study the coal seam located in the northern part of Jharia Coalfield of Dhanbad district. This method has been applied on experimental basis to know the efficacy of this technique. The improvement of resistivity methods using multi-electrode arrays led to an important development of electrical imaging for subsurface surveys. Such surveys are usually carried out using a large number of electrodes, i.e., 48 or more, connected to a multi-core cable. Apparent resistivity measurements are recorded sequentially sweeping any quadripole (current and potential electrodes) within the multielectrode array. As a result, high-definition pseudosections with dense sampling of apparent resistivity variation at depths are obtained in a short time. It allows the detailed interpretation of 2-<i style="">D</i> resistivity distribution in the ground. In this experimental study, Syscal Junior Switch-48 electrode resistivity meter is used for the exploration of the coal seam at east Basuria colliery of Jharia coal field, Dhanbad. Pole-dipole configuration of the multielectrode resistivity survey has been carried out along two traverses R1 and R2, which were selected over developed workings of coal seam II at an incline mine of the east Basuria colliery. These traverses lie in dip-rise direction with station interval of 2.5 m. Coal seam is delineated having high resistivity values ranging more than 989 to 1632 ohm.m at depths varying 10 to 31 m from the surface.