Case research in reservoir geophysics: developing new rock physics templates through electrical resistivity description using integrated seismic and mechanical properties

Electrical resistivity is one of most significant parameters that have a vital role in subsurface studies, such as determining porosity, permeability, saturation, and facies. This research was carried out in a carbonate zone, holding a reservoir with approximately ۱۰۰ m thickness, using well-logging data. All variations in the electrical resistivity are investigated using seismo mechanical changes in the study area. The electrical resistivity log used in this research is lateral log deep (LLD) in order to minimize the effect of the mud filtrate. At first, changes in density (Rhob), seismic velocities consist of P and S – wave velocity (VP and VS, respectively), and acoustic impedance (AI) are evaluated using electrical resistivity and porosity. Then, the variations of statistic elastic modules, including Young (E), Bulk (K), and shear (M) modules, and Poisson ratio (PR), are investigated on electrical resistivity and porosity scales. After that, the static elastic modulus and PR changes are evaluated against the S- wave velocity on the electrical resistivity scale. The Vs-E template showed a more regular variation on the electrical resistivity scale than other plots. Then, the shear impedance (SI) changes against AI are assessed separately on three scales: electrical resistivity, VP, and porosity. Finally, three rock physics templates, VS – E on the AI scale and SI –AI on the P – wave velocity and porosity scales, are developed as local rock physics models to evaluate the electrical resistivity. Furthermore, the results show that PR is not a suitable parameter to evaluate electrical resistivity in the studied zone

Keywords:

Electrical properties , Seismic parameters , Mechanical features , Rock physics , Carbonate reservoir.