Microstructural Influences on the Stress Sensitivity of Crystalline and Sedimentary Rocks

P002 Microstructural Influences on the Stress Sensitivity of Crystalline and Sedimentary Rocks O. Gaede* (Freie Universitaet Berlin) S. Shapiro (Freie Universitaet Berlin) D. Dewhurst (CSIRO Petroleum) S. Stanchits (GeoForschungsZentrum Potsdam) & A. Siggins (CSIRO Petroleum) SUMMARY Understanding the stress dependence of elastic rock properties is an essential tool for various applications in the earth sciences and the resource industries. The stress sensitivity approach presented here derives the nonlinear stress-strain relationship for a porous medium by considering the stress induced changes of the pore geometry. We compare the stress dependence of ultrasonic velocity measurements for three rock samples that were specifically