Sensitivity studies in forward AVO modeling

Abstract

AVO is commonly used as an exploration tool to detect hydrocarbons. AVO is a function of several rock and fluid parameters such as compressional velocities, shear wave velocities, and densities. The AVO response is therefore sensitive to errors in these rock and pore-fluid properties. The rock parameters are often associated with uncertainties, which may be due to measurement errors or heterogeneities in the rocks. Since some of these rock properties are often estimated from other rock properties, uncertainties may be caused by use of imperfect models in the estimation. BiotGassmann’s equations of fluid-substitution are used at an intermediate stage in the AVO forward modeling, to predict the compressional and shear wave velocities of hydrocarbonsaturated rocks from reference dry or brine-saturated rock properties. These equations, too, are sensitive to various rock and fluid properties.