Rock Physics Based Interpretation of Seismically Derived Elastic Volumes
A rock physics based seismic interpretation workflow has been developed to extract volumetric rock properties from seismically derived P- and S-wave impedances, Ip and Is. This workflow was first tested on a classic rock physics velocity-porosity model. Next, it was applied to two case studies: a carbonate and a clastic oil field. In each case study, we established rock physics models that accurately relate elastic properties to the rock’s volumetric properties, mainly the total porosity, clay content, and pore fluid. To resolve all three volumetric properties from only two inputs, Ip and Is, a site-specific geology driven relation between the pore fluid and porosity was derived as a hydrocarbon identifier. In order to apply this method at the seismic spatial scale, we created a coarse-scale elastic and volumetric variables by using mathematical upscaling at the wells. By using Ip and Is thus upscaled, we arrived at the accurate interpretation of the upscaled porosity, mineralogy, and water saturation both at the wells and in a simulated vertical impedance section generated by interpolation between the wells.
Dr. Jack Dvorkin is Program Leader for Rock Science Program at the College of Petroleum Engineering and Geosciences at King Fahd University of Petroleum and Minerals in Saudi Arabia. He is an SEG Honorary Member. He holds a Ph.D. in Continuum Mechanics from Moscow University. He has developed many of the current theoretical rock physics models used for physics-based interpretation of seismic impedance inversion data for porosity, mineralogy, and pore fluid. Jack’s research has been focused on effective-medium models for the elastic and transport properties of natural rocks; rock physics of gas hydrate deposits; theoretical models for attenuation and velocity dispersion of seismic waves; pore pressure prediction from seismically derived attributes, tectonophysics, and experimental and digital rock physics. He has published over 170 technical papers, 5 books, and 9 U.S. patents. He has supervised 30 Ph.D. and M.S. students.