东昆仑东段中更新世以来的成山作用及其动力转换  

Mountain Building and Its Dynamic Transition Since Middle Pleistocene in East of Eastern Kunlun, Northeast Tibet Plateau

作　　者：王国灿[1] 侯光久[1] 张克信[1] 朱云海[1] 

机构地区：[1]中国地质大学地球科学学院,湖北武汉430074

出　　处：《地球科学（中国地质大学学报）》2002年第1期4-12,共9页Earth Science-Journal of China University of Geosciences

基　　金：国家自然科学基金 (No .40 0 72 0 6 2 );国土资源部重点科技项目"新生代区域地质调查新方法研究 (No .2 0 0 0 2 0 1-2 -2 )";国土资源部"1:2 5万阿拉克湖幅区域地质调查"项目

摘　　要：对东昆仑造山带东段第四纪构造及与地貌关系的分析表明 ,现代山盆相间的地貌格局成型于中更新世 ,且在中更新世以来发生了多次构造变形体制的转换 .根据布青山北部查干额热格地区第四系剖面的构造、地层时代及地层与构造关系的分析表明 ,中更新世时期为伸展构造体制 ,昆仑山内部开始发生了差异隆升 ,布青山开始崛起 .中更新世末应力体制发生急剧变化 ,由伸展体制转为收缩事件 ,又急速转为伸展构造体系 ,短暂的收缩事件造成了中更新世冲洪积层的褶皱 ,随后的伸展则导致了影响深刻的向北依次断落的阶地状正断层系统 .晚更新世应力体系再度发生重大转换 ,伸展正断层体系被左旋走滑运动体系所代替 ,并一直延续至今 .中更新世以来多次隆升构造变形体制的转换说明东昆仑地区的成山过程受控于多种动力背景 ,而非单一的挤压抬升 .The analysis of the relationship between the Quaternary structure and the relief in the east of eastern Kunlun reveals that the modern relief framework with alternating basins and ridges were formed in the Middle Pleistocene. Multiple deformation system changes have occurred since that time based on the analysis of the structures, strata age and the relationship between structures and rocks from a well displayed Quaternary cross section. In the Middle Pleistocene, the N S extension caused differential uplifting in the Kunlun Mountains. The Buqingshan and Buerhanbudashan popped up the plateau plane. At the end of the Middle Pleistocene,the stress system changed quickly from N S extension to N S compression, then to extension again. The short N S compression event caused folding of the Middle Pleistocene strata on the northern side of Buqingshan,and southward, the thrust folding on its southern side. Soon after the compression event, the N S extension appears again, leading to the step normal faults on the northern side of the Buqingshan and the graben horst assemblage, which overprinted to the previous thrust fold assemblage in the Tertiary Guide Group of the southern slope of the Buqingshan . While in the Late Pleistocene, an important change occurred again in the stress system. The E W transpressive sinistral strike slip faults became active and has remained till now. The multiple age stress change during Quaternary suggests that the uplift mechanism and the mountain building processes are multiplex and complex.

关 键 词：第四纪 隆升构造 成山作用 更新世 东昆仑造山带 

分 类 号：P542.2[天文地球—构造地质学]