Rock physics & Interpretation

[RP-09] Rock Physics Modeling of Silicious and Carbonate Facies: Conceptual AVO Models Applied to Reservoirs Around the Globe

*Alan J Mur¹, Lev Vernik¹ (1. Ikon Science (United States of America))

We assembled and expanded a database of siliciclastic log data and published laboratory measurements on dry carbonate samples to demonstrate micromechanics-based methods of rock physics modeling of carbonate rocks coming from diverse depositional and diagenetic environments. By focusing on the effects of mineralogy, porosity, pore shapes, and effective stress on elastic properties of limestones and dolomites in a wide 2-45% porosity range, we show that the Vernik-Kachanov rock physics model (RPM), previously developed for siliciclastics, can be successfully used in seismic reservoir characterization of carbonates worldwide. This rock physics model adheres to the strict micromechanics principles (effective field theory) and allows us to account for realistic pore shapes and separate them from the effects of cracks. Because of the very diverse pore geometries typically observed in carbonates, we use thin section image analysis yielding pore perimeters and areas, which allow us to constrain the pore stiffness represented by the pore shape factors. We subdivide, wherever feasible, the database into textural and mineralogical facies and analyze differences and similarities between them in terms of elastic modeling, which may be utilized in AVO inversion-based reservoir characterization efforts worldwide.