Sand-resistivity/conductivity and saturation evaluation in laminated formations with biaxial anisotropy

摘要

Disclosed herein are embodiments of systems, methods, and computer program products for evaluating sand-resistivity and/or sand-conductivity, as well as saturation in laminated shale-sand formations with biaxial anisotropy (BA) in resistivity. In one embodiment, the method determines sand resistivity (R_sd) of the laminated shale-sand formation directly from triaxial resistivities (R_x, R_y, and R_z) of the laminated shale-sand formation based on a bimodal model with BA anisotropy. In another embodiment, the method determines sand resistivity (R_sd) directly based on a bimodal model with transverse isotropy (TI) anisotropy using the triaxial resistivities, horizontal resistivity, and vertical resistivity (R_x, R_y, R_z, R_h, and R_v). In another disclosed embodiment, the above methods may be used to perform quality control on a determined sand-resistivity and saturation of a laminated shale-sand formation.