Multiple Porosity Differential Effective Medium Models – Improvements and Approximations

E-18 MULTIPLE POROSITY DIFFERENTIAL EFFECTIVE MEDIUM MODELS – IMPROVEMENTS AND APPROXIMATIONS. Summary 1 The Xu-White model (Xu and White 1995) is a widely used Differential Effective Medium (DEM) petrophysical model based on the scattering theory of Kuster and Toksöz (1974). A rock model is built by adding small increments of sand-related or clay-related porosity to a medium. The elastic properties are recalculated after each addition up to the desired porosity. To this model we have added microcracks with pore aspect ratios typically much less than 0.01 to handle pressure effects on the rock frame. We add increments of pores of