干旱区生态环境知识资源中心(Arid): 天山山前主要推覆构造区的地壳缩短

Arid

	天山山前主要推覆构造区的地壳缩短
其他题名	CRUSTAL SHORTENING OF MAJOR NAPPE STRUCTURES ON THE FRONT MARGINS OF THE TIANSHAN
	杨晓平; 邓起东; 张培震; 徐锡伟
ISSN	0253-4967
出版年	2008
卷号	30 期号:1 页码:111-131
中文摘要	利用平衡地质剖面方法研究天山山前主要褶皱带的地壳缩短,其中3条平衡剖面分别横跨天山南簏的柯坪逆断裂-褶皱带和库车逆断裂-褶皱带,2条剖面横跨天山北簏的玛纳斯活动逆断裂-褶皱带,其余1条剖面横跨吐鲁番中央隆起逆断裂-褶皱带.柯坪活动逆断裂-褶皱带、库车逆断裂-褶皱带、玛纳斯逆断裂-褶皱带和吐鲁番盆地的地壳缩短量分别为 40～45km、27～37km、8.5～10.5km和6～7km.天山山前活动逆断裂-褶皱带在EW向上互不重叠,它们的缩短量大致代表了该经度上新生代的最小地壳缩短量,反映出天山地壳缩短由西向东减小的趋势.假定天山山前活动逆断裂-褶皱带开始形成的时间为距今2.5Ma的西域砾岩沉积期,考虑到博阿断裂、塔拉斯-费尔干纳断裂在SN向上的缩短活动分量,上述4个地段的最小缩短速率分别为 15.4～17.3mm/a、12.7～16.5mm/a、3.8～4.5mm/a和2.3～2.7mm/a.活动走滑断裂在天山内部特定位置向左偏转,走向由NW转为NWW,在断裂转折的部位走滑活动量转化为天山SN向的缩短变形.
英文摘要	We present the results of selected balanced cross-sections across four active reverse fault-fold belts at the front margins of the Chinese Tianshan,an intracontinental mountain belt formed in response to the India-Eurasia continental collision. It consists of Paleozoic,Mesozoic and Cenozoic strata in active fold-and-thrust belts at two sides of Tianshan, and the stratum in active fold belt changes younger from west fold-and-thrust belt to east. The middle part’s structure is complicated in Kalpin active fold-and-fault belt,the width gradually diminishes towards east. At the west of Akesu city,the Kalpin active fold-and-thrust belt vanishes, but at the east part of Akesu city,the Kuche active fold-and-thrust belt emerges on the Tarim desert. In the middle section of the Kuche active fold-and-thrust belt near Baicheng County,the structure is most complicated,and the width is also maximal. The width of Kuche fold-and-thrust belt gradually decreases towards east,and disappears near 85° longitude line. But at the northern piedmont of Tianshan,the Manas active fold-and-thrust belt presents itself approximately at the same longitude. The longitude of the west end of Turpan centre uplift active fold-and-thrust zone is approximately the longitude of the east end of the Manas active fold-and-thrust belt. The four active fold-and-thrust belts which we studied are located at the north and south sides of Tianshan Mountains. Two balanced cross-sections traverse the Kalpin active fold-and-fault belt and one crosses the Kuche fold-and-fault belt. Two balanced cross-sections cross the Manas active fold-and-thrust belt,and one balanced cross-section crosses the Turfan centre uplift zone. The crustal shortening of Kalpin fold-and-thrust belt is 40～45km,that of Kuche fold-and-thrust belt about 27～37km,and of Manas,Turpan centre uplift active fold-and-thrust belt are 8.5～10.5km and 6～7km,respectively. The four active fold-and-thrust belts at south and north Tianshan are not superposed in longitude. So their crustal shortenings approximately represent the minimal crustal shortening of Tianshan at different segments,and also reflect the reducing trend of crustal shortening from west to east. It is very difficult to calculate the crustal shortening across entire Tianshan,owing to deficiency of data about active reverse fault and strike-slip fault within Tianshan Mountains. If the time of initial deformation is the starting time of Xiyu conglomerate deposition(since 2.5Ma),and considering the shortening component on south-north direction of Bo-A NW strike-slip fault,the minimum crustal shortening rates at four segments of Tianshan would be 15.4～17.3mm/a,12.7～16.5mm/a,3.8～4.5mm/a and 2.3～2.7mm/a,respectively.
中文关键词	天山 ; 地壳缩短 ; 逆断裂-褶皱带 ; 缩短速率 ; 第四纪
英文关键词	Tianshan crustal shortening active fold-and-thrust belt Quaternary
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOSCIENCES MULTIDISCIPLINARY
WOS研究方向	Geology
CSCD记录号	CSCD:3243640
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/222164
作者单位	中国地震局地质研究所, 北京 100029, 中国
推荐引用方式 GB/T 7714	杨晓平,邓起东,张培震,等. 天山山前主要推覆构造区的地壳缩短[J],2008,30(1):111-131.
APA	杨晓平,邓起东,张培震,&徐锡伟.(2008).天山山前主要推覆构造区的地壳缩短.,30(1),111-131.
MLA	杨晓平,et al."天山山前主要推覆构造区的地壳缩短".30.1(2008):111-131.