Real time microseismic monitoring to study geomechanics of underground structures

Abstract

The study of Geomechanics of underground structures in real time requires capture of fracture information well in advance from structure failure to initiate remedial measures during development and after completion of structure. The advanced high dynamic range microseismic instrumentation with latest Computer methods/algorithms helped to investigate strata behaviour in real time. One such investigation was carried out at the Rajendra longwall underground coal mine, Madya Pradesh state India and addressed major concerns of the mines like roof falls, stability of workings, goaf caving process etc,. The results of this study demonstrated that microseismic monitoring is very useful in understanding the geomechanics of underground structures. Among the several seismic source parameters obtained, the reliable precursor found was the microseismic Event Release Rate (ERR) of micro fractures before failure, which is the most significant instability indicator of underground structure. Results from this work can be useful to other underground structures such as tunnels and LPG storage caverns.