New model explaining inverted source mechanisms of microseismic events induced by hydraulic fracturing

Abstract

We present a case study of detailed source mechanism inversion in microseismic dataset from hydraulic fracturing of a shale gas play. This study uses surface monitoring array to invert shear and non-shear parts of the source mechanisms from 75 individual events to characterize relationship between hydraulic fracture and induced seismicity. We observe source mechanisms dominated by shear failure with dip-slip and strike-slip sense of motion. We propose a new model explaining source mechanisms induced by hydraulic fracturing based on bedding plane slippage.