Stress mechanism of microseismic events during hydraulic fracture stimulation for unconventional hydrocarbon reservoirs

I have processed a total of nine thousand microseismic events to investigate the stochastic process of the stress mechanism as well as frequency-magnitude relation between microseismic, volcanic and intraplate events. The processed data was composed of all available three components data with magnitude range from 0.4 <M< 6.5 extracted from the Incorporated Research Institution of Seismology (IRIS) and from a producing resevoir in the Middle East with magnitude range from -2.3 <M< -0.5. Seismic b-values are estimated using the maximum likelihood method (Aki, 1965) while the stress drops are derived from Brune's source model (Brune, 1970). Volcanic and intraplate regions were selected in order to understand the fracture mechanism between the two regions with the hope to further correlate with the recorded microseismic events in the hydrocarbon reservoir. The results show that b values and stress drop for the volcanic region are lower than those of the intraplate region, while b-values for microseismic events are the highest. The results also show strong dependency with seismic moment and corner frequency values from each regions. From all the results, this study provides a better understanding and some possible features to distinguish microseismic events during hydraulic stimulation.