喀什北缘南天山冲断带构造变形分析  

Structural Deformation of Fold-Thrust Belt in the North Margin of Kashi,Southern Tien Shan

作　　者：钱俊锋[1] 肖安成[1] 程晓敢[1] 王亮[1] 张微[1] 孟立丰[1] 姚琪[1] 

机构地区：[1]浙江大学地球科学系

出　　处：《中国矿业大学学报》2008年第4期538-544,共7页Journal of China University of Mining & Technology

基　　金：“十五”国家重点科技攻关项目(2004BA616A02-01-02)

摘　　要：综合利用地震剖面解释和地面地质资料分析，揭示了位于喀什北缘南天山冲断带的结构和变形特征．结果表明，从平面上可以将该冲断带划分为喀拉伯克托尔-温古尔、托帕-康西维尔、阿图什和喀什等多排背斜，其中阿图什及其北侧的背斜带由源于沿中寒武统阿瓦塔格组内部滑脱的7中断层系由北向南的活动所控制；从剖面上可以将该冲断带划分为2个不同层次的推覆构造系统：浅层为大规模叠瓦式冲断系统，滑脱面从寒武系逐渐抬升到新近系；深层为隐伏的双重冲断构造系统，底板和顶板断层分别位于寒武系和古近系底部喀什群的石膏层中．利用构造变形分析方法和平衡剖面技术，确定了各背斜带空间展布及深浅层2个不同冲断系统的构造样式，得出研究区在上新世以来南北缩短量为32．64～49．1km，缩短率为40．5％～50．51％，地壳平均缩短速率为9．11～13．71mm／a．The structural and deformational features of fold-thrust belt in the north margin of Kashi, southern Tien Shan were disclosed based on various data such as 2D seismic profile and field geologic survey. The results show that the fold-thrust belt can be divided into several rows of anticlines, including Kaboketuoer-Wenguer, Tuopa-Kangxiweier, Atushi and Kashi on plane, and the development of Atushi anticlines and its north side are controlled by the activity of the thrust system originated along the middle Cambrian Awatage group from north to south. The fold-thrust belt can be divided into two different spatial levels： the shallow tectonic is a large scale imbricate thrust system, the detachment surface is uplifted from Cambrian system to Neogene system; the deep structure is a buried duplex structure system, the faults in floor and roof are located at gypsic horizon in Cambrian and Neogene system respectively. Based on the structural deformation analyzing and balanced section technology, the distribution of each anticlinal belts and the structure style of the low and deep thrust systems are confirmed. In this area the distance is shortened by 32.64-49.1 km from north to south since Pliocene with the scalage of 40.5%-50.51% ,and its average crustal shortening rate is 9.11-13.71 mm/a.

关 键 词：南天山冲断带 构造变形 平衡剖面 构造建模 

分 类 号：P54[天文地球—构造地质学]