The Pressure Dependence of Acoustic Velocity – a New Petrophysical Model

Pressure dependence of acoustic waves is an extensively explored rock physical problem. Knowledge of the phenomena of pressure dependence is an important prerequisite for relating laboratory meas-urements to in-situ rock properties, and for interpreting seismic measurements in terms of subsurface petrophysical parameters. Therefore it’s expedient to develop a petrophysical model based on simple physical assumptions which describes the relationship between acoustic velocity and pressure. The model is based on the idea that microcracks are opened and closed besides different pressure states. The model was applied on own acoustic velocity data sets and also data sets measured by Yu et al. as well as Xu et al. The material parameters of the models are determined by using inversion method and the laboratory measurements were compared to the theoretical data. The theoretical data matched accurately with measured data proving that the petrophysical model applies well in practice.