Self-adapting extraction of matrix mineral bulk modulus and verification of fluid substitution

摘要

Gassmann’s equations are commonly used for predicting seismic wave velocity in rock physics research. However the input matrix mineral bulk modulus parameters are not accurate, which greatly influences the prediction reliability. In this paper, combining the Russell fluid factor with the Gassman-Biot-Geertsma equation and introducing the dry-rock Poisson’s ratio, we propose an effective matrix mineral bulk modulus extraction method. This method can adaptively invert the equivalent matrix mineral bulk modulus to apply the Gassmann equation to fluid substitution of complex carbonate reservoirs and increase the fluid prediction reliability. The verification of the actual material fluid substitution also shows that this method is reliable, efficient, and adaptable.