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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。
The western part of the East Kunlun Mountains is one of the areas with a low degree of geological research in northwestern China. Through the structural analysis of typical sections, we can draw the following important recognitions: ① Well-developed faulting system in the western part of East Kunlun Mountains. The main deformation events in this area are thrusting, normal sliding and detachment. ② Thrust faulting began in the Late Carboniferous and Late Triassic during the Early Jurassic, but intense activity occurred in the mid-Miocene Quaternary during the intense depression in the Kumkur Basin. (3) The structural pattern of northward thrusting and southward normalizing is consistent with the overall tectonic structure in the northern part of the Qinghai-Tibet Plateau. It is also similar to the structural pattern of the Himalayas in the southern margin of the Qinghai-Tibet Plateau. However, the direction of thrust expansion is opposite , Strong thrust expansion occurred in the mid-Pliocene to Quaternary India plate collision strongly with the Eurasian Plate and the rapid uplift of the Qinghai-Tibet Plateau. The reverse thrust expansion and positive slip reveal the kinematic characteristics of the symmetrical extension of the deep material on both sides of the Qinghai-Tibet Plateau and the gravity sliding of the surface material to the hinterland of the plateau. Therefore, the establishment of the fault tectonic system in this area provides a train of thought for studying the deep process of the northern part of the Qinghai-Tibet Plateau and establishing a unified geodynamic model for the uplift of the Qinghai-Tibet Plateau.