| Title | Geomechanically Coupled Simulation of Flow in Fractured Reservoirs |
|---|---|
| Authors | C. A. BARTON, D. MOOS, L. HARTLEY, S. BAXTER, L. FOULQUIER, H. HOLL, R. HOGARTH |
| Year | 2013 |
| Conference | Stanford Geothermal Workshop |
| Keywords | reservoir fracture characterization, stress-sensitive fractures |
| Abstract | Geological, geophysical, geomechanical, and reservoir engineering data are used to characterize the in situ stresses, the natural fracture network and the controls on fracture permeability in geothermal reservoirs. As most fractures are stress-sensitive, their hydraulic conductivities will change with changes in bottomhole flowing and reservoir pressures, causing variations in production profiles between wells. Flow properties are a function of effective fracture aperture, so it is possible to predict reservoir behavior using the relationship between the mechanical behavior of natural fractures (in response to in situ stress and pore pressure changes) and their hydraulic properties. Low flow rate injection tests may be used to determine the hydraulic properties of the fractures. Flow through the individual fractures which form a connected network are explicitly modeled for an EGS reservoir. Fracture stress sensitivity was coupled to the flow simulation through a DFN with dynamic adjustment of aperture to effective normal and shear stresses (after Moos and Barton 2008) and calibrated with microseismic data (positions and times of events) and injection data (rates and pressures). The results highlight the importance of combining all available data, including microseismic, wellbore image, and flow and stimulation test data, to determine reservoir flow behavior and its response to stimulation. |