Characteristics of Lower Paleozoic strike-slip faults and their significance for oil and gas exploration in Xunyi-Yijun area, Ordos Basin

• Published in: Shi you shi yan di zhi Vol. 46; no. 2; pp. 342 - 353
• Main Authors: Qichao WANG, Guangxiang LIU, Jiang WU, Xinxin YUE, Ziming SUN, Juntao ZHANG, Xiaopeng GAO, Ling LIU, Kai LU, Zhongpei ZHANG
• Format: Journal Article
• Language: Chinese
• Published: Editorial Office of Petroleum Geology and Experiment 01.03.2024
• Subjects: fault characteristic; formation mechanism; lower paleozoic; oil and gas exploration; ordos basin; strike-slip fault; xunyi-yijun area
• ISSN: 1001-6112
• DOI: 10.11781/sysydz202402342

In recent years, the Ordos Basin has undergone a reevaluation, transitioning from a perception of a single block to a focus on understanding the influence of multiple stages and fault systems on hydrocarbon accumulation. This study utilizes the latest 3D seismic and drilling data alongside a theoretical model of strike-slip fault to analyze fault geometry and kinematics in the Xunyi-Yijun area of the basin's southern region. The mechanisms of fault formation are predicted and the related impacts on the formation and accumulation of deep carbonate rocks are also discussed. The results indicate the presence of three fault systems in the Xunyi-Yijun area, with decoupling between deep and shallow layers. The Lower Paleozoic strike-slip faults exhibit distinct characteristics, including high vertical structure, dip swing, and a "flower-shaped" structure in the section. The faults display "compression shear in the northwest, tension shear in the center, and segmental deformation on trunk fractures" on their planes.