Prediction of rock elastic moduli based on a micromechanical finite element model

Abstract

We present a finite element simulation approach to compute rock elastic moduli that is based on a grain-grain contact methodology, moving away from the common approach of modeling the solid framework as a whole, thus, the individual grains are not distinguished. In this approach we are able to address the grain-grain contact problem associated with the different degrees of consolidation found in reservoir rocks. Three important elements in this workflow are, a robust grain-grain segmentation method, a conformal meshing algorithm, and the grain-grain contact physics. We present benchmark results in four cases from literature and compare with laboratory and other results from elastic solvers that do not model explicitly grain-grain contacts. Finally, we discuss options to estimate and model the strength of the contacts, relating to the degree of consolidation of the rocks.