The dependence of reservoir permeability and porosity on pressure can have a significant impact on well performance. This paper addresses this issue theoretically, via reservoir simulation, and via production data analysis type curves. This paper presents the single phase fluid flow equation for a slightly compressible fluid in a stress sensitive reservoir in a form which can be solved in Laplace space to generate profiles of well flow rate versus time (for constant bottomhole pressure production). This is achieved by writing the flow equation in terms of the derivatives of a function involving the sum of pressure and pressure-squared terms. Reservoir simulation results concur with the theoretical prediction that depletion in a stress sensitive reservoir will be slower than in a non-stress sensitive reservoir, however ultimate recovery in the simulation cases was not affected by stress sensitivity. p/z plots for stress sensitive reservoirs show volumetrics are unaffected by stress sensitivity. Analysis of simulated production data from stress sensitive reservoirs shows that drainage area is likely to be underestimated by this approach. Permeabilities predicted from analysis using standard type curves are lower than the permeability at initial reservoir pressure. The magnitude of the reduction in the interpreted permeability naturally depends on the magnitude of the stress sensitivity.

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