Reliable input data for reservoir simulation of production-induced changes
in matrix and fault permeabilities are essential for the successful plannin
g and management of oil and gas reservoirs. Withdrawal and injection of res
ervoir fluid causes a change in pore pressure, which in turn changes the 3D
effective-stress state. The stress path followed by the reservoir controls
the evolution of the effective-stress state, and with it the changes in st
resses, which cause reservoir-rock deformation and permeability changes. A
stress-sensitive simulation that uses a nonlinear finite-element geomechani
cal model coupled to a finite-difference fluid-now simulator reveals the ef
fects on the reservoir performance by dynamic changes in permeability and t
he reactivation of faults.