塔里木盆地顺北地区11号走滑断裂带变形及其活动特征  

Deformation and Activity Characteristics of the No.11 Strike-slip Fault Zone in the Shunbei Area, Tarim Basin

作　　者：况安鹏 余一欣[2,3] 朱秀香[1] 陈石[2,3] 金峰 梁鑫鑫 余浪 KUANG Anpeng;YU Yixin;ZHU Xiuxiang;CHEN Shi;JIN Feng;LIANG Xinxin;YU Lang(SINOPEC Northwest Oilfield Company,Urumqi,Xinjiang830011,China;State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing102249,China;College of Geosciences,China University of Petroleum,Beijing102249,China)

机构地区：[1]中国石化西北油田分公司,新疆乌鲁木齐830011 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [3]中国石油大学(北京)地球科学学院,北京102249

出　　处：《现代地质》2021年第6期1809-1817,共9页Geoscience

基　　金：国家重点研发计划项目(2017YFC0603105);中国石化西北油田分公司科技项目(KY2019-S-099)。

摘　　要：塔里木盆地顺北地区发育大量走滑断裂带,并对油气的运聚成藏有重要控制作用。以顺北西部地区地震资料为基础,对顺北11号走滑断裂带的几何变形特征、活动性、活动期次及其形成机制等进行了分析。顺北11号走滑断裂带整体呈NNW走向延伸,具有垂向分层性和平面分段性。断裂带北段主体为压扭和张扭交互段,中段为两条次级断层控制的拉分地堑,南段由数条分支断层构成马尾状构造。顺北11号断裂带整体活动性由北向南减弱,运动学标志显示是一条右旋走滑断层。顺北11号断裂带主要经历了晚奥陶世和晚志留世-中泥盆世两期活动,部分地区的活动持续到石炭纪。顺北11号走滑断裂带的活动性和运动学特征与塔北地区NNW走向的走滑断裂体系比较相似,而不同于塔中地区的NE向左行走滑断裂体系。顺北11号走滑断裂带的形成主要受控于塔里木盆地北部天山洋多期俯冲挤压而产生的自北向南的挤压应力,断裂自北向南扩展延伸,类似于顺北5号走滑断裂带的北段。Strike-slip faults are widely developed in the Shunbei area, Tarim Basin, which play an important role in the hydrocarbon migration and accumulation. In this study, based on 3 D seismic data interpretations of the western Shunbei area, the profile and plane geometry features, fault activity, active periods, and formation mechanism of the Shunbei-11 fault are characterized and analyzed. The Shunbei-11 fault extends to NNW for over 100 km, and is characterized by vertical/horizontal segmentation: The northern part is dominated by coeval transpression and transtension;two secondary faults formed a pull-apart graben in the middle part;a horsetail splay consists of several terminated branching faults in the southern part. The fault activities differ in deep and shallow layers, and decrease generally from south to north. The surface fault zone propagates from north to south, and the kinematic signatures suggest that it is a dextral strike-slip fault. Shunbei-11 fault underwent multiple active stages, and most of the fault has experienced two stages in the Late Ordovician(pre-T;) and Late Silurian-Middle Devonian(pre-T;), while some parts were active till Carboniferous. In terms of activity and kinematic features, the fault is similar to the NNW-trending strike-slip system of the Tabei uplift, but different from the NE-trending sinistral strike-slip system in the Tazhong uplift. Under the principal compressive stress(from north to south), and originated from the multistage collision of the South Tianshan Ocean north of the basin, the fault propagated from north to south, and the way of development and propagation was similar to that of the northern part of the Shunbei-5 fault.

关 键 词：顺北地区 走滑断裂带 分段性 活动性 形成机制 

分 类 号：TE121.2[石油与天然气工程—油气勘探]