Stress Mechanism of Microseismic Events during Hydraulic FractureStimulation for Unconventional Hydrocarbon Reservoirs

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