Simulation of Hydraulic Stimulation of Fractured Reservoir and Induced Seismicity using Discrete Element Fracture Network Model

Abstract

This paper presents discrete element fracture network model designed to simulate hydraulic fracturing and induced seismicity in crystalline fracture rock mass at great depth. Among many tested, results from three fluid injection scenarios are examined which include (i) spatiotemporal distribution of induced seismic events, (ii) moment magnitudes, (iii) source mechanisms, (iv) stress drop of induced events. Comparisons are made with field observations from literatures, 1) to examine how close the model is capable of capturing and reproducing the field EGS induced seismicity; 2) to have an idea how large magnitude induced events, in particular in post-shutin period, can be mitigated by changing the style of injection; and finally 3) to examine the potential (also limitations) of the presented methodology for more practical use in EGS research and industry.