阿尔金断裂带东段构造抬升与青藏高原北缘扩展

As a major boundary fault zone, the Altyn Tagh fault zone (ATF) has directly affected neotectonic features of the northern margin of Qinghai-Tibet Plateau. The kinematics of the ATF has drawn much attention. It is well-known that the scale of the sinistral strike-slip is key factor for the interpretation of the different deformation modes of Qinghai-Tibet plateau, therefore the kinematics studies of the ATF have mostly been concerned with the sinistral strike-slip rate of the ATF. There are a lot of rivers crossing with the ATF, the previous studies of the terraces related with the ATF are mainly located on the horizontal offset of the terraces in order to obtain sinistral-slip rate。 As a structural zone with strike-thrust characteristic, the ATF is a dividing structure of the northern margin of Qinghai-Tibet Plateau, and its thrusting and uplifting movement is signification for controlling the uplift of the northern margin of the Plateau. Therefore the uplifting studies of the ATF will be helpful for understanding the uplift model and mechanism, and promote the modern kinematic study of the northern margin of the Plateau. The tectonic uplifting along the eastern segment of the ATF is main research content in this project. Based on the surveying of geomorphy and dating of stream terraces, the evolution of space and time of uplifting along the eastern segment of the ATF will be obtained. This research is helpful for undertanding the integrated dynamics of the northern margin of Qinghai-Tibet Plateau, and provide theoretical significance for understanding and improving the mechanism of tectonic evolution, uplifting and extending of the northern margin of Qinghai-Tibet Plateau.

阿尔金断裂带是一条具有逆冲性质的巨型左旋走滑断裂带。其作为青藏高原北缘的边界活动构造带，构成高原与其北邻的塔里木盆地、敦煌盆地等不同地貌和构造单元的自然分界。以往有关断裂带的运动学研究只集中在其左旋走滑上，缺乏与构造抬升相关的运动学研究。本项目以阿尔金断裂带东段为研究地点，以断裂带的构造抬升活动为主要研究内容，以河流阶地为对象，通过地貌测量及地貌面年龄测定，研究阿尔金断裂带东段自晚更新世以来的抬升活动，获取此时间段内断裂带逆冲活动在时间和空间上的变化。此项研究有助于我们完整理解青藏高原北缘的运动学特征，对于理解和完善高原北缘的构造演化机制、隆升机制、高原扩展，有着较为重要的理论意义。