Analysis of the Influencing Factors on Electrical Properties and Evaluation of Gas Saturation in Marine Shales: A Case Study of the Wufeng-Longmaxi Formation in Sichuan Basin

Accurate gas saturation calculations are critical to evaluating the production of marine shale reservoirs. As a high-resolution exploration method, geophysical resistivity well-logging technology has been widely applied in almost all types oil/gas reservoirs evaluate formation fluid saturation. Although calculated saturations accurate for conventional reservoirs, it is challenging task acquire due presence complex rock compositions and types. It necessary analyze different influencing factors on electrical properties establish more applicable model shales. In this work, we make full use geological data, well logging experiment data Wufeng-Longmaxi Formation Sichuan Basin, China. Six conductive studied, including stratigraphic structures, clay minerals, pyrite, organic matter, pore fluids. Then, conductivity developed, which high- low-resistivity layers connected parallel. Based model, new method stepwise stripping proposed calculate Finally, by interpreting two wells, compared calculation results methods demonstrate accuracy method. The show that thin, layers, pyrite overmature carbonized matter reduce weaken contribution fluids measured resistivity. Moreover, better than Archie’s equation, Simandoux’s neutron-density porosity overlay findings paper will help gain insight into mechanism responses improve estimated