Geological and Geotechnical Characterisation Using Geophysical Logs – An Example from Adriyala Longwall Project of Singareni Collieries, India

Abstract

The studies conducted at Adriyala longwall block of Singareni Collieries Company Limited (SCCL) in the state of Telangana, India conclude that geophysical logs comprising electrical, density, neutron, caliper, Full Waveform Sonic (FWS) and acoustic images can provide reliable geological and geotechnical models required for longwall mining. The P wave velocities obtained from sonic logs are correlated with the lab determined strength parameters such as uniaxial compressive strength (UCS), Tensile Strength (TS) and Young's Modulus. The empirical equations provided a means to construct UCS map of interburden strata of coal seams from sonic data. The integrated study of various maps prepared from geological and geophysical inputs provided an effective means to analyse the competency of immediate overburden and roof of Seam-I, which is considered for longwall mining. Back analysis of behaviour of strata will allow developing of predictive models and appropriate strata control strategies to be applied at Adriyala and other mines and also for multiseam extraction.