四川盆地中部走滑断裂系统及其控油气作用  

Strike-slip fault system and its control on oil&gas accumulation in central Sichuan Basin

作　　者：管树巍[1] 姜华[1] 鲁雪松[1] 梁瀚 朱光有[1] 崔俊峰[1] 金惠[1] 雷明[1] 陈涛[3] 杨荣军 Guan Shuwei;Jiang Hua;Lu Xuesong;Liang Han;Zhu Guangyou;Cui Junfeng;Jin Hui;Lei Ming;Chen Tao;Yang Rongjun(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;Research Institute of Exploration and Development,PetroChina Southwest Oil&Gas Field Company,Sichuan Chengdu 610041,China;PetroChina Research Institute of Petroleum Exploration and Development-Northwest,Gansu Lanzhou 730020,China;Research Center of Sichuan Basin,PetroChina Research Institute of Petroleum Exploration and Development,Sichuan Chengdu 610094,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油西南油气田公司勘探开发研究院,四川成都510041 [3]中国石油勘探开发研究院西北分院,甘肃兰州730020 [4]中国石油勘探开发研究院四川盆地中心,四川成都610094

出　　处：《石油学报》2022年第11期1542-1557,共16页Acta Petrolei Sinica

基　　金：中国石油天然气股份有限公司科学研究与技术开发项目(2021DJ0504,2021DJ0301,2021DJ0204)资助。

摘　　要：四川盆地中部(川中地区)的走滑断裂与多层系油气聚集关系密切。系统阐述走滑断裂的性质、特征、分布规律、成因与演化机制对于深化川中地区断裂系统控藏与控富集研究,以及完善四川盆地复合含油气系统理论具有重要意义。研究在川中地区下—中三叠统膏盐岩层内部识别出深层走滑断裂的伴生构造,以及导致上震旦统灯影组台缘错动的走滑断裂行迹。研究表明,深层走滑断裂与其伴生构造之间存在2种组合关系,据此识别出6条主干左行走滑断裂带。通过分析代表性生长构造的局部构造活动(LSA)沉降量变化,将川中地区的断裂演化划分为5个阶段:1晚震旦世同沉积断裂阶段;2早奥陶世—早二叠世右行走滑阶段;3晚二叠世—早三叠世伸展走滑断裂阶段;4中—晚三叠世走滑活动沉寂阶段;5中侏罗世至今左行走滑阶段。走滑断裂是控制川中地区多层系立体差异化成藏的关键因素。在晚二叠世—早三叠世伸展走滑断裂阶段,安岳裂陷槽内筇竹寺组烃源岩进入生油高峰,原油沿灯影组台缘及NWW向断裂带充注成藏;在中侏罗世至今左行走滑阶段,特别是晚白垩世以来,深层走滑活动在下—中三叠统膏盐岩层及上覆地层内形成伴生构造,控制了浅层陆相致密油气的分布,同时派生出的NE向伸展破裂则造成深层原油裂解气垂向运移至龙王庙组,甚至在栖霞组、茅口组聚集成藏,形成"上富下贫"的油气成藏模式。The strike-slip faults are closely related to the multi-layered hydrocarbon accumulation in central Sichuan Basin.A systematic description of the properties,characteristics,distribution,genesis and evolution mechanism of strike-slip faults is of great significance for deepening the study on controlling hydrocarbon accumulation and enrichment by fault system in central Sichuan Basin,and improving the theory of composite petroleum system in Sichuan Basin.This study identifies the associated structures of deep strike-slip faults in the Lower-Middle Triassic gypsum-salt bed,as well as the structural traces of strike-slip fault activities leading to the platform margin dislocation of Upper Sinian Dengying Formation in central Sichuan Basin.The study shows that there are two combinations between the deep strike-slip faults and their associated structures,based on which six main sinistral strike-slip fault zones are identified.Based on analyzing the subsidence changes of the representative growth structures caused by local structural activity(LSA),the fault evolution in central Sichuan Basin can be divided into five stages:(1)the synsedimentary fault stage in Late Sinian;(2)the dextral strike-slip stage from Early Ordovician to Early Permian;(3)the extensional strike-slip fault stage from Late Permian to Early Triassic;(4)the strike-slip activity silent stage in Middle-Late Triassic;(5)the sinistral strike-slip stage from Middle Jurassic to present.Strike-slip fault is the key factor controlling the multi-layered multidimensional differential accumulation in central Sichuan Basin.In the extensional strike-slip fault stage from Late Permian to Early Triassic,the source rocks of Qiongzhusi Formation in Anyue aulacogen reached the oil generation peak,and the crude oil was charged and accumulated along the platform margin of Dengying Formation and NWW-trending fault zone.In the sinistral strike-slip stage from Middle Jurassic to present,especially since Late Cretaceous,the deep strike-slip activities formed associated struc

关 键 词：膏盐岩层 走滑断裂 伴生构造 雁列构造 灯影组台缘 LSA沉降量 立体成藏 川中地区 

分 类 号：TE122.3[石油与天然气工程—油气勘探]