A petrophysical model of shales considering soft-mineral aspect ratios and its application
YANG Qi-Yu1,2(), LI Jing-Ye1,2, WU Fan1,2, LI Wen-Jin1,2, CUI Jin-Ming1,2
1. State Key Laboratory of Petroleum Resource and Prospecting,Beijing 102249,China 2. College of Geophysics,China University of Petroleum(Beijing),Beijing 102249,China
Previous petrophysical modeling of shale reservoirs often ignored the influence of pore types and soft-mineral aspect ratios on the elastic modulus.This study built a petrophysical model for transversely isotropic shales considering pore types and shapes,and soft-mineral aspect ratios.In this study,solid minerals were divided into hard and soft minerals,and soft minerals'anisotropic characteristics and shape changes were considered.According to the actual conditions of reservoirs, pores were categorized into intragranular,organic,and intergranular pores,and they were classified into stiff and soft pores based on their shapes.Finally,the input parameters were inverted using the particle swarm optimization algorithm to further calculate compressional and shear wave velocities,anisotropy parameters,and rock mechanical parameters.Combined with the actual data application,the results of this study were compared with the known results of shear wave velocity and isotropic rock mechanical calculation,suggesting that the model in this study is effective.
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YANG Qi-Yu, LI Jing-Ye, WU Fan, LI Wen-Jin, CUI Jin-Ming. A petrophysical model of shales considering soft-mineral aspect ratios and its application. Geophysical and Geochemical Exploration, 2024, 48(1): 98-104.
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