塔里木盆地中央隆起带断裂系统分析

摘要

Based on interpretation of seismic profiles, the structural styles, distribution and deformation characteristics of main fault systems in different periods in the Central uplift of Tarim Basin have been analysed in details. Our research will help for establishing links between development of Central uplift belt fault systems and peripheral orogenic belt evolution, and clarifing the dynamic background of the fault systems development Moreover, a new classification of fault deformation style in the Central uplift of Tarim Basin is presented in this paper. Two sets of regional decollement structures are identified in the southern flank of Bachu uplift, in which the shallow Serikbuya-Mazhatage decollement fault system, the leading fault of the present southwestern Tarim foreland thrust system, thrusted onto the southern flank of Bachu uplift We found a set of huge arc-shaped foreland thrust fault system protruding northwestward in the middle-east of Tanggubas depression and the east of Tazhong uplift The thrust fault system is bounded by Che'erchen fault in the southeastern Tarim Basin and mainly occurred in the end of Late Ordovician. The leading faults of the thrust fault system are characterized by cover-bed decollement and thrusting, and cut northwest trending faults, such as Tazhong I fault belt, Tazhong 10 fault belt, Tazhong 2 fault belt and Tazhong 22 fault belt which were formed in the Late Early Ordovician and are featured by basement-involved style. Integrated with the significant tectonic events adjacent orogenic belts, these fault systems in Tarim Basin can be classified into three sets with respect to the West Kunlun orogenic belt, South Tianshan orogenic belt and Altyn orogenic belt respectively.%本文以地震剖面解释为基础,深入分析塔里木盆地中央隆起带主要断裂带的构造样式和变形特征,确定不同时期断裂系统的分布规律,并试图建立中央隆起带断裂系统发育与周缘造山带演化之间的联系,进而阐明其发育的动力学背景.论文提出了塔里木盆地中央隆起带断裂构造变形样式分类体系;在巴楚隆起的南部边缘,识别出两套区域性的盖层滑脱构造系统,其中浅层色力布亚-玛扎塔格滑脱冲断层逆冲到巴楚南部边缘之上,并构成了现今塔西南前陆冲断系的锋缘断裂;发现了分布在塘古巴斯坳陷的中东部和塔中隆起东部的、规模巨大的、向北西方向凸出的弧形逆冲断裂系统.该弧形逆冲断裂系统的东南部以车尔臣断裂为界,主要形成于晚奥陶世末期,锋缘断裂以盖层滑脱逆冲为特征,与早奥陶世末期发育的、呈NW向展布的塔中Ⅰ号断裂带、塔中10号断裂带、塔中2号断裂带和塔中22号断裂带等构成的基底卷入式逆冲断裂形成明显的交切关系;论文将周缘造山带的重大构造运动事件与塔里木盆地内部不同时期发育的断裂系统相对比,在塔里木盆地内划分出分别与西昆仑造山带、阿尔金造山带和南天山造山带相关的三套断裂系统.