Modeling nonlinear response of fractured rocks and reservoirs

Since the early work of Athey (1930), there have been many attempts to describe the various nonlinear behaviors of rocks and soils in terms of functionals having only a few parameters, while nevertheless being able to fit the complicated available data with satisfactory accuracy. Such approaches have not been universally applied however, and the present analyses are intended to draw attention to the possibility of using such nonlinear fitting methods on old as well as new data sets. In particular, some special emphasis is placed here on re-examining the well-known laboratory data of Coyner (1984) on rocks in light of such modeling tools, and we find that the nonlinear approach again has several clear advantages - especially in terms of reducing the number of variables needed to describe the observed behavior of both bulk modulus and porosity of rocks undergoing large changes in pressure. (C) 2016 John Wiley & Sons, Ltd.