四川盆地南部泸州—云锦地区走滑断裂构造变形特征  

Structural characteristics of strike-slip faults in the Luzhou-Yunjin area,southern Sichuan Basin

作　　者：田方磊 梁虹 臧殿光 刘欢 巫芙蓉 何登发[1] 刘鹏 刘珍 张伟康 司阳涛 陈浩凡 Tian Fangei;Liang Hong;Zang Dianguang;Liu Huan;Wu Furong;He Dengfa;Liu Peng;Liu Zhen;Zhang Weikang;Si Yangtao;Chen Haofan(School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083;Southwest Geophysical Research Institute,BGP,CNPC,Chengdu 610213;Southwest Geophysical Company,BGP,CNPC,Chengdu 610213)

机构地区：[1]中国地质大学(北京)能源学院,北京100083 [2]中国石油集团东方地球物理勘探有限责任公司西南物探研究院,成都610213 [3]中国石油集团东方地球物理勘探有限责任公司西南物探分公司,成都610213

出　　处：《地质科学》2024年第3期804-818,共15页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金重点项目“上扬子克拉通盆地深层新元古代裂谷体系的结构、成因及其控油气作用”(编号:42330810)资助。

摘　　要：以多重滑脱褶皱冲断构造为主要变形的泸州—云锦地区同样发育走滑断裂。逆冲构造和走滑断裂的分类、分期厘定对于重新认识泸州—云锦地区的断裂系统具有重要意义。以泸州—云锦地区的高精度三维地震数据、钻测井数据为基础,通过平面—剖面结合精细构造解析和井—震标定分析,获得如下认识:1)北东向、北西向、近南北向等不同走向、不同级别的逆断层和褶皱带叠加、复合变形,构成了泸州—云锦地区网状的多重滑脱冲断褶皱构造变形系统。2)区内主要发育4条走滑断裂带,断层对关键界面的改造呈现出微小伸展地堑的变形特征,在剖面上则主要表现出“Y”字形负花状构造的变形样式。其中,蜀南1号走滑断裂带近南北走向,在左旋剪切作用下形成;蜀南2号、3号走滑断裂带由多条次级断层带或小型正断层左阶斜列构成,形成于右旋剪切背景。蜀南1号、蜀南2号、蜀南3号走滑断裂带均形成于二叠系沉积前(相当于泥盆纪—石炭纪)。蜀南4号走滑断裂带则呈北东走向,主体沿着背斜带的脊部发育,在右旋剪切作用下发育,形成于二叠系沉积后(相当于早-中三叠世)。蜀南4号断裂带、蜀南3号断裂带的局部区段以及主体发育在二叠系—三叠系内的逆冲断层,对志留系、二叠系、三叠系的多套源储组合具有良好的沟通作用;同时,它们对断控缝洞型储集层的形成具有积极影响,利于二叠系栖霞组、茅二段、嘉陵江组等多层系的油气聚集成藏。Multiple layers detached thrust and fold systems dominated the deformation of the Luzhou-Yunjin area,while,strike-slip faults also developed in the area.Precise plane-section interpretation and classification of thrust faults and strike-slip faults are of great significances for understanding deformation patterns and fault systems of the area.Through structural interpretation and well-seismic calibration analysis based on high-precision 3D seismic data and drilling data,conclusions are as follows:1)the superimposing deformation of reverse faults and fold belts with different grades and strikes of NEE,NW,near EW,etc.,constitute the multi-layer detached thrust and fold system in Luzhou-Yunjin area.2)Four main strike-slip fault zones developed in the area,presenting the deformation features of extensional grabens on planes and the“Y”shaped negative flower structures on sections.Among them,the No.1 strike-slip fault zone is nearly north-south strike,and formed under left-lateral shear.While,the No.2 and No.3 strike-slip fault zones are composed of multiple secondary fault zones or small normal faults with left-step arrangements,which formed under the regional right-lateral shear background.The No.1,No.2 and No.3 strike-slip fault zones in southern Sichuan Basin was formed before the Permian(inferred as Devonian to Carboniferous).On the other hand,the No.4 strike-slip fault zone that developed along the ridge of anticline was formed under right-lateral shear after Permian(inferred during the Early to Middle Triassic).The No.4 strike-slip fault zone and local segments of the No.3 strike-slip fault zone,as well as the thrust faults that mainly developed in the Permian-Triassic provided effect migration pathways for multiple sets of sources and reservoirs.And they also resulted in the formation of fault-controlled fracture-cavity reservoirs,which in general are beneficial to gas accumulation in reservoirs of Qixia Formation,2nd member of Maokou Formation,and Jialingjiang Formation,etc.

关 键 词：走滑断裂 褶皱冲断构造 成因机制 油气 泸州—云锦地区 四川盆地南部 

分 类 号：P542[天文地球—构造地质学]