Influencing mechanism of saline sediments on pore system formation and evolution in terrestrial shales

• DOI: 10.1016/j.petsci.2023.06.010
• Publication Date: 2023-07-03T22:33:51Z
• Authors: Yu-Qi Wu; Fu-Jie Jiang; Di Chen; Jing Guo; Chen-Xi Zhu; Zhao Zhao; Zhuo-Yue Yan; Tao Hu
• Keywords: Halite; Anhydrite

The majority of oil and gas resources in the world are related to saline sediments, which mainly occur sedimentary strata form cap rocks or salt-associated shales. A large number shale have been discovered sediments Cenozoic terrestrial lake basin China. hydrocarbon generation ability reservoir capacity control generation. is characterized by pore type, structure porosity. Most China's belong salt-bearing formations. role gypsum-salt formation evolution organic matter (OM) such formations has received extensive attention. However, systematic understanding lacking. Research on under action rock especially weak. Taking shales third member Shahejie Formation (Es3) Bohai Bay Basin as an example, influence halite process pores was studied this paper. results show that gypsum minerals were associated with OM, made them more likely develop OM pores. samples a high mineral content (HC) developed regarding volume specific surface area than those low HC. thick salt influenced factors deep thermal brine upwelling, sea erosion arid environments. frequent alternation between humid environments led outbreak death organisms precipitation rock, formed simultaneous deposition minerals. Finally, we established model participation contribute development both Stage II IV. This study provides strong microscopic evidence for system reservoirs.