库车坳陷秋里塔格构造带中段变形特征及构造意义:基于野外调查和地震剖面构造解析  

Deformation Characteristics and Structural Significance of the Middle Qiulitage Structural Belt in the Kuqa Depression:Based on Field Investigation and Structural Interpretaion of Seismic Profiles

作　　者：张治鑫 吴珍云 邓寒潇 汪伟[3] 王洪艳 贺婉慧 李慧欣 毛可奕 董少春[3] 尹宏伟[3] ZHANG Zhixin;WU Zhenyun;DENG Hanxiao;WANG Wei;WANG Hongyan;HE Wanhui;LI Huixin;MAO Keyi;DONG Shaochun;YIN Hongwei(Jiangxi Provincial Key Laboratory of Genesis and Prospect for Strategic Minerals,East China University of Technology,Nanchang 330013,China;School of Earth Sciences,East China University of Technology,Nanchang 330013,China;School of Earth Sciences and Engineering,Nanjing University,Nanjing 210023,China;Tianshui Institute of Geology and Mineral Resources,Gansu Buerau of Geology and Exploration of Non-ferrous Metals,Tianshui 741020,China)

机构地区：[1]战略性矿产成矿理论与深部预测江西省重点实验室东华理工大学,南昌330013 [2]东华理工大学地球科学学院,南昌330013 [3]南京大学地球科学与工程学院,南京210023 [4]甘肃省有色金属地质勘查局天水矿产勘查院,天水741024

出　　处：《高校地质学报》2025年第2期213-228,共16页Geological Journal of China Universities

基　　金：深地国家科技重大专项课题(2024ZD1003306);国家自然科学基金(41602208、42372264和42072320);江西省教育厅科学技术研究项目(GJJ210702)及东华理工大学博士启动基金项目(DHBK2019053)联合资助。

摘　　要：库车坳陷秋里塔格构造带中段(中秋)位于库姆格列木群和吉迪克组两套膏盐层沉积交汇区域,以盐水沟为界,其东、西两侧构造变形样式差异明显,推断具有构造转换特征。基于野外调查,结合地震剖面解析,对中秋构造特征开展了精细解析,进一步厘定了中秋构造转换特征,阐明了盐上层和盐下层差异化构造转换机制。结果表明,中秋盐上层主要经历了两期构造作用:康村组末至库车组初,以褶皱变形为主,主要形成了在中秋错位排列的库车塔吾背斜和南秋里塔格背斜;库车组初到第四纪,以逆冲断层作用为主,在断层作用下,背斜进一步隆升变形,并逐步形成了由南向北依次分布的构造前缘带、南部隆起带、压扭核心带和北缘平缓带。压扭核心带构造变形最为剧烈,东、西两侧的差异性构造样式指示该地带可能发育走滑断裂,以释放两侧地层差异位移引发的压扭应力。中秋盐上层构造转换模式为同向倾斜型,即在相同倾向断层之间存在位移传递,使地表褶皱出现扭曲、分叉等特征。盐下层构造转换主要通过逆冲断层沿走向延伸距离的变化和断层倾角变化来完成。中秋盐上层和盐下层构造转换受到膏盐层控制,盐层在东西方向上的多层分布和厚度变化是导致库车塔吾背斜和南秋里塔格背斜发育位置不同的重要原因;南秋里塔格背斜盐下断层在双盐层控制下,向南延伸距离更远,库车塔吾背斜盐下断层受单盐层控制,延伸距离相对较短。The middle Qiulitage structural belt(Zhongqiu belt)in the Kuqa Depression is located in the overlapping area of the Kumugeliemu(K1-2 km)salt and Jidike(N1 j)salt.Divided by the Yanshui river of the Zhongqiu belt,significant differences in structural deformation styles are presented on the eastern and western sides,inferred that there are structural transformation characteristics.Based on field geological investigations and structural interpretation of seismic profiles,the structural characteristics of the Zhongqiu belt are analyzed in detail,and the structural transformation characteristics of the Zhongqiu belt are further determined,and the differentiated structural transformation mechanism between the suprasalt and subsalt strata is clarified.The results show that the suprasalt strata in the Zhongqiu belt experienced two stages of structural evolution.The first stage was dominated by folding deformation from the end of the Kangcun Formation(N1k)to the early Kuqa Formation(N2k),primarily forming the Kuqa-Tawu anticline and southern Qiulitage anticline arranged in an offset pattern in the Zhongqiu belt.The second stage was primarily dominated by thrust faulting from the early N2k to the Quaternary.Under the effect of fault activities,the anticlines were further uplifted and deformed,gradually forming the front zone,uplift zone,torsional core zone,and gentle slope zone,distributed sequentially from south to north in the Zhongqiu belt.The structural deformation of the torsional core zone is the most severe,and the different structural styles on the eastern and western sides indicate that strike-slip faults may develop in this zone to release the compression-torsion stress caused by the differential displacement on both sides.The structural transfer model of suprasalt strata in the Zhongqiu belt is characterized as a synthetic type,where displacement is transferred between faults with similar dip angles,leading to features such as twisting and branching of surface folds.The subsalt structural transformation is mainl

关 键 词：构造转换带 构造解析 盐构造 构造转换机制 库车坳陷 

分 类 号：P542[天文地球—构造地质学]