东昆仑阿其克库勒湖地区的逆冲扩展作用

东昆仑西段是我国西北地区地质研究程度较低的地区之一。通过典型剖面的构造分析，可以得出下列几点重要认识：①东昆仑西段具有十分发育的断裂构造系统，逆冲扩展、正滑作用和拆离作用是该区的主要变形事件。②逆冲断裂起始于晚石炭世和晚三叠世—早侏罗世时期，但强烈活动发生在库木库里盆地强烈坳陷的中新世—第四纪时期。③该区北向逆冲扩展作用和南向正滑作用并存的构造格局，和青藏高原北部的总体构造格局相一致，与青藏高原南缘喜马拉雅地区的的构造格局也十分类似，但逆冲扩展方向相反，强烈逆冲扩展作用都发生在中—上新世至第四纪印度板块与欧亚板块强烈碰撞和青藏高原急剧隆升时期。这种方向相反的逆冲扩展和正滑作用揭示青藏高原深层物质向南、北两侧对称式扩展和表层物质向高原腹地重力滑动的运动学特征。因此该区断裂构造系统的建立对研究青藏高原北部的深部作用过程，建立青藏高原隆升的统一的地球动力学模式提供了一种思路。

Thrust Propagation in the Aqqikkol Lake Area, East Kunlun, Northwestern China

The western sector of the East Kunlun is one of the less studied regions in northwestern China. A structural analysis of the typical sections shows that, 1. There is a very well-developed fault system in the western sector of the East Kunlun, and thrust propagation, normal slip and decoupling were the main deformation events in the area; 2. Although thrusting in the area started in the Late Carboniferous and Late Triassic-Early Jurassic, strong activity took place in the Miocene-Quaternary when the Kumkol basin was strongly downwarped; and 3. The tectonic pattern of the coexistence of N-directed thrust propagation and S-directed normal slipping in the area is consistent with the general tectonic pattern of the northern Qinghai-Tibet plateau and also very similar to the tectonic pattern of the Himalaya region on the southern margin of the Qinghai-Tibet plateau, but, the directions of thrust propagation are opposite. All the strong thrust propagation occurred in the Mio-Pliocene to Quaternary, a period of strong collision of the Indian plate and Eurasian plate and abrupt uplift of the Qinghai-Tibet plateau. This oppositely directed thrust propagation and normal slipping reveal the kinematic characteristics of a symmetric propagation of deep-seated materials beneath the Qinghai-Tibet plateau toward the northern and southern sides, and gravitational sliding of superficial materials toward the interior of the plateau. Therefore, the establishment of the fault system in the area may provide an approach to the study of the deep process in the northern Qinghai-Tibet plateau and construction of a unified geodynamic model of the uplift of the Qinghai-Tibet plateau.