海相油气地质2025，Vol.30Issue(6)：599-612,14.DOI:10.3969/j.issn.1672-9854.2025.06.006
川南地区深层走滑断裂的判识及其地质意义
Identification and geological significance of deep strike-slip faults in southern Sichuan Basin
摘要
Abstract
The Permian System in the southern Sichuan Basin serves as the primary target for major natural gas reserve growth in the region.Recent significant breakthroughs in syncline zone have demonstrated that high-yield gas reservoirs in southern Sichuan Basin are not completely controlled by positive structural belts.Instead,strike-slip faults have some control effects on karst paleogeomorphology,high-quality reservoir development and natural gas enrichment in southern Sichuan Basin.However,because the large fold-thrust zones on the shallow surface result in the low seismic resolution and the weak seismic reflection,the strike-slip fault and the characteristics are difficult to determine,and the controlling effect on natural gas enrichment and high yield is unknown,which seriously restricts the exploration and development of fault-controlled gas reservoirs in this area.Therefore,based on artificial intelligence fault identification technology,this paper carries out the identification of deep strike-slip faults,determines the identification marks of strike-slip faults,implements the distribution and characteristics of strike-slip faults in southern Sichuan Basin.Moreover,the controlling effect of strike-slip faults on high-yield gas reservoirs is analyzed based on actual drilling data.The results show that:(1)The artificial intelligence method based on deep learning can improve the identification accuracy of deep hidden strike-slip faults,and can effectively identify hidden strike-slip faults under thrust structures in southern Sichuan Basin.(2)Four planar identification marks and five sectional markers for strike-slip faults in southern Sichuan Basin are defined,thus verifying the development of a rhombus strike-slip fault system in the pre-Permian strata,with a total length of 940 km.(3)The strike-slip fault in southern Sichuan Basin has obvious classification,stratification and staging characteristics.There develop various types of structure such as linear structure,en echelon structure,flower structure and fault horst.Under the geological background of multi-stage extension-convergence,the strike-slip faults develop inheritively from the tension-torsion of the Sinian-Cambrian to the compression-torsional of the Upper Cambrian-Upper Ordovician on the basis of the weak zone of the early basement.(4)The strike-slip fault can connect multiple sets of source rocks in the Cambrian and Silurian,which plays an important role in controlling oil and gas migration and accumulation,and controls the distribution of high-yielding gas reservoirs of the Permian Maokou Formation together with the Permian reverse fault.Deep Cambrian-Ordovician strike-slip faults are a key factor for the high enrichment and productivity of fracture-cave type gas reservoirs controlled by faults in southern Sichuan Basin.关键词
走滑断裂/人工智能断裂识别/天然气成藏模式/二叠系/川南Key words
strike-slip fault/artificial intelligence fault identification/gas accumulation model/Permian/southern Sich-uan Basin分类
能源科技引用本文复制引用
李海,周小军,隆辉,邬光辉,刘田,邓敏,李成海..川南地区深层走滑断裂的判识及其地质意义[J].海相油气地质,2025,30(6):599-612,14.基金项目
本文受国家自然科学基金项目"克拉通盆地内部走滑断层的成因机制与发育模式"(编号:U24B2019)、中国石油-西南石油大学创新联合体科技合作项目"深层超深层碳酸盐岩气田勘探开发基础理论与关键技术研究"(编号:2020CX0101)联合资助 （编号:U24B2019）
