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1.
利用GPS数据反演阿尔金断裂现今滑动速率 总被引：2，自引：0，他引：2
《地震地质》2015,(3)
利用2009—2013年的GPS水平速度场,使用三维线性球面弹性块体模型,综合前人研究成果建立了阿尔金断裂及其邻区的三维块体几何模型,反演得到阿尔金断裂不同断层段和其邻区主要活动断裂的现今滑动速率。结果表明:阿尔金断裂柴达木盆地以南段左旋走滑速率为(7.8±0.2)mm/a,该段向北至肃北左旋走滑速率为(7.5±0.1)mm/a,肃北—昌马段左旋走滑速率为5.3~5.5mm/a,昌马以北段的左旋走滑速率仅有(1.0±0.4)mm/a。阿尔金断裂左旋走滑速率总体表现出从南向北减小的趋势,衰减主要集中在祁连山地区,并转换为这一地区明显的地壳挤压作用。 相似文献
2.
阿尔金断裂带地处西藏、新疆、青海、甘肃交界的阿尔金山脉地区,西起新疆与西藏交界的拉竹龙,向北东东方向斜切昆仑山及祁连山,东端隐没于巴丹吉林沙漠之下.是中国西部一条著名的北东东向左旋走滑断裂带.阿尔金断裂由多条长达数百公里的断裂组合而成,卫星影像上主干断裂具有舒缓波状的线性特征,地面上以狭窄断层谷、断层崖分布为特点.现今阿尔金断裂带的形成和印度次大陆与欧亚大陆的碰撞和持续推挤以及青藏高原的隆升有关,是青藏高原西北边界的断裂之一. 相似文献
3.
东昆仑断裂带、阿尔金断裂带、祁连山一海原活动断裂带等组成了青藏高原北部大型走滑断裂系。这些断裂之间的空间联系、巨大的走滑量及其地壳缩短特征,都显示了它们在印度板块和欧亚板块汇聚过程中青藏高原的形成扮演了主要角色。这些断裂准确的滑动速率对于研究青藏高原变形和演化过程,确定水平滑动、变形的规模,建立高原的变形和演化模式提供了重要依据。 相似文献
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5.
阿尔金断裂在河西走廊西端的酒西盆地附近左旋走滑特征逐渐消失,而其东侧的宽滩山断裂和黑山北缘断裂表现为逆冲构造。在宽滩山北侧分布的2条断裂,分别是塔尔湾-池家刺窝断裂和干峡山断裂,这2条断裂也表现出明显的活动特征。前人认为塔尔湾-池家刺窝断裂是1条低活动速率的逆冲断裂,并未对其水平运动进行详细研究。宽滩山北缘断裂带是否存在水平走滑运动,对于进一步探讨阿尔金走滑断裂和祁连山北缘逆冲断裂的构造转换模式,具有非常重要的意义。文中通过无人机Sf M摄影测量等野外工作,对宽滩山北缘的塔尔湾-池家刺窝断裂和干峡山断裂的走滑运动特征进行研究,并获得了2点初步认识:1)宽滩山北缘断裂是具有右旋兼有逆冲的活动断裂,通过对宽滩山北缘断裂带的河流冲沟和阶地的位错量进行统计,初步估计其晚更新世右旋走滑速率为0.2~0.25mm/a,全新世右旋走滑速率为0.5~1.5mm/a;2)宽滩山北缘断裂所在的河西走廊西端位置的构造主要驱动力来自于祁连山向北的挤压作用,造成了宽滩山北缘断裂的右旋走滑和酒西盆地内多条断裂的逆冲运动性质。 相似文献
6.
论述了祁连山构造带新生代以来的变形过程及形成机制。研究表明：祁连山构造带的变形过程是在欧亚大陆与印度大陆碰撞汇聚作用下发生和发展的,其过程与整个青藏高原的隆升过程同步进行。其中阿尔金断裂在其东段的走滑贯通对祁连山－河西走廊地区的构造运动影响很大。上新世末或第四纪初阿尔金断裂东段的走滑导致了祁连山地区的应力场的旋转,进而增大了沿ＮＷＷ向主断裂的水平走滑分量。它是引起主断裂发生走滑的重要原因之一。 相似文献
7.
阿尔金断裂带作为青藏高原北部边界 ,其走滑量和走滑速率一直为地学界所关注 ,对这样一条大陆内部巨型走滑断裂带的滑动速率进行研究 ,对于了解阿尔金断裂带左旋走滑和青藏高原北部隆升之间的耦合关系 ,具有重要意义。在阿尔金断裂带东段的疏勒河口以西 ,阿尔金断裂错断了几条规模相近的河流阶地和洪积扇 ,形成典型的走滑断层断错地貌。通过对这些典型断错地貌点的地貌观测和年代学研究 ,得到阿尔金断裂带东段石堡城以东疏勒河以西自 2 0kaBP以来的滑动速率约为 4～ 5mm/a。自 50kaBP以来 ,阿尔金断裂带东段断层平均滑动速率具有较高的时间、空间一致性 ,约为 4～ 6mm/a ,表明利用河流阶地和洪积扇位错作为断层走滑位移标志计算断层滑动速率 ,具有较高的可信度 相似文献
8.
阿尔金活动断裂带东段的滑动速率由西向东逐渐减小,而肃北是阿尔金断裂东段滑动速率的"突变点"之一。在肃北以东分布多条分支断裂,野马河北侧断裂便是其中的一条。野马河北侧断裂长约30km,总体走向NEE,该断裂沿野马河盆地北侧山前洪积扇延伸,沿断裂具有大量的左旋走滑和逆冲等地貌现象,多处冲沟出露有断层剖面。野外调查结果表明该断裂是一条左旋走滑兼逆冲断裂,错断了晚更新世时期形成的洪积扇或冲沟阶地。通过实测得到地貌面左旋、垂直错动数据,并采集样品测试相关地貌面的年龄,估算该断裂晚更新世以来的平均水平滑动速率为(1.27±0.18)mm/a,平均逆冲速率为(0.4±0.07)mm/a,该断裂分解了阿尔金断裂东段的部分运动量 相似文献
9.
在挤压应力的背景下,龙门山断裂带南段的米亚罗断裂在汶川地震序列过程中却发生了大量的走滑型地震。为研究其原因,分区反演了米亚罗断裂附近的应力张量。结果显示:米亚罗断裂南北两侧主压应力轴走向近乎垂直于龙门山断裂带走向,倾角近水平;主张应力轴走向近竖直。而米亚罗断裂主压应力轴走向为SWW-NEE,倾角近水平;主张应力轴走向为NNW-SSE,倾角近水平,与该断裂受到左旋剪切力的应力状态相符。据此推测米亚罗断裂在汶川地震序列过程中的活动是由于该断层两侧受力不均衡导致撕裂引起的。为理解以上分区内余震的破裂模式,将各区余震的矩张量进行叠加得到各区的综合地震矩张量,发现米亚罗断裂南侧与北侧综合地震矩张量各分量分布趋势相似(表明其破裂模式具有一致性),且南侧大部分分量大于北侧,尤其是垂直于龙门山断裂带走向的水平压缩分量和竖直方向的膨胀分量,说明南侧向SE逆冲的分量大于北侧的对应分量,两者的差异导致了米亚罗断裂的撕裂,并且这种撕裂的分量与南北两侧逆冲分量的差异大致在同一量级,故完全可以由南北两侧的逆冲差异解释其活动原因。根据以上研究提出了能对上述现象进行解释的米亚罗断裂活动的动力学模型。 相似文献
10.
断裂晚第四纪滑动速率及现今GPS观测揭示了青藏高原向北扩展与高原边缘隆升的运动特征.主要断裂晚第四纪滑动速率及跨断裂GPS应变速率的结果表明,青藏高原北部边缘的断裂以低滑动速率（＜10 mm/a）为主,特别是两条边界断裂：阿尔金断裂和海原—祁连山断裂.两条主要边界断裂上的滑动速率分布显示了断裂间滑动速率转换及调整特征.阿尔金断裂自95°E以西的8～12 mm/a稳定滑动速率,向东逐渐降低到最东端的约1～2 mm/a,而海原断裂自哈拉湖一带开始发育后滑动速率为1～2 mm/a,到祁连一带（101°E以东）增大到相对稳定的4～5 mm/a,直到过海原后转向六盘山一带,滑动速率降低到1～3 mm/a,甚至更低.滑动速率的变化及分布特征显示,阿尔金断裂滑动主要是通过祁连山内部隆起及两侧新生代盆地变形引起的缩短来吸收的,海原—祁连山断裂的低滑动速率及沿断裂运动学特征表明断裂尾端的陇西盆地变形及六盘山的隆起是断裂左旋走滑速率的主要吸收方式.这一变形特征表明,青藏高原北部边缘的变形模式是一种分布式的连续变形,变形发生自高原内部,边界断裂的走滑被高原内部变形所吸收. 相似文献
11.
Did the Altyn Tagh fault extend beyond the Tibetan Plateau? 总被引：2，自引：0，他引：2
Brian J. Darby Bradley D. Ritts Yongjun Yue Qingren Meng 《Earth and Planetary Science Letters》2005,240(2):425-435
The pre-Miocene northeastern termination of Altyn Tagh fault is a critical outstanding problem for understanding the mechanics of Cenozoic deformation resultant from the Indo-Asian collision and mechanisms of Tibetan Plateau formation. Structures beyond the widely accepted NE end of the Altyn Tagh fault, near the town of Yumen, are needed in order to accommodate strike-slip deformation related to plate-like lateral extrusion tectonics, but structures with the necessary slip magnitudes and histories have not been identified. We report on a series of newly recognized and documented E to ENE-striking faults within the Alxa block, NE of the Tibetan Plateau, that are visible on remotely sensed images and confirmed by field studies. These structures are demonstrably left-lateral faults based on offset geology and kinematic indicators such as striae and s-c fabrics in fault gouge. The faults have post-Cretaceous offsets of at least tens to possibly > 150 km, but limited post-Miocene displacement, constrained by offset sedimentary basins. These characteristics suggest that strike-slip faults of the Alxa region have a similar structural history as the central-eastern Altyn Tagh fault and can provide a mechanism for accommodating Oligocene-Early Miocene extrusion along the Altyn Tagh fault. 相似文献
12.
Chen Zhengle Zhang Yueqiao Chen Xuanhua Wang Xiaofeng Ramon A. S. Zack W. B. 《中国科学:地球科学(英文版)》2001,44(1):103-111
The ENE-striking Altyn Tagh fault (ATF), extending along the northern edge of the Ti-betan Plateau, is one of the major important strike-slip faults, and has been known as one of the key areas to debate the eastward extrusion and crustral shortening models of the Tibetan Plateau during and after India-Asia collision. This paper mainly presents new evidence of Late Cenozoic sedimentary process to reconstruct the slip history of the ATF during the Late Cenozoic. Field measurements and laboratory analyses of the sedimentary characteristics in the Late Cenozoic basins in the central Altyn Tagh fault suggest that Late Cenozoic sedimentary sequence should be divided into three units according to facies changes. The paleo-topography reconstruction shows that the sedimentarion in these basins was tightly related with the fault, indicating that the ATF has experienced at least three stages of strike slipping in the Late Cenozoic. New geological data from the Late Cenozoic sedimentary basins and the formation of the present Suo’erkuli basin provide evidence for the displacement of the fault. The result shows that the 80–100 km left-lateral strike-slip displacement of the fault has been accumulated in the Late Cenozoic.
相似文献13.
青藏高原中北部的巴颜喀喇地块是近年来强震最为活跃的地区,自1997年以来在地块周围发生了一系列7级以上地震.2014年于田MS7.3级地震就发生在该地块西边界附近的硝尔库勒盆地南缘,该区是阿尔金断裂、康西瓦断裂和东昆仑断裂等多组不同走向大型走滑活动断裂带的交汇部位,不同断裂走向的突然转变及滑动速率差异使该地区形成局部的拉张应力状态,发育了多条NE和近SN向的左旋正断裂. 通过余震分布、震源机制解结果等资料分析,认为此次地震的发震构造为阿尔金断裂西南端的一条次级断裂——硝尔库勒断裂,地震破裂特征为左旋走滑兼正断性质. 在巴颜喀喇地块这一轮的强震活动中,其北边界和东边界都显示块体向东挤出约7 m的位移量,但块体西边界产生的伸展量明显与整个块体向东的位移量不协调,2014年于田MS7.3级地震是巴颜喀喇地块向东挤出的构造响应和应变调整.模拟结果显示阿尔金主断裂上的库仑应力有所增加,东昆仑—柴达木地块可能为下一个强震活跃区,特别是阿尔金断裂的中西段,是今后应该重点关注和监视的地区. 相似文献
14.
THE PALEOSEISMIC SURFACE RUPTURE AT SOUTH OF CENTRAL ALTYN TAGH FAULT AND ITS TECTONIC IMPLICATION 
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下载免费PDF全文 SHAO Yan-xiu YUAN Dao-yang LIU-ZENG Jing Jerome Van der Woerd LI Zhi-gang WU Lei LIU Fang-bin 《地震地质》1979,42(2):435-454
In this study, we described a 14km-long paleoearthquakes surface rupture across the salt flats of western Qaidam Basin, 10km south of the Xorkol segment of the central Altyn Tagh Fault, with satellite images interpretation and field investigation methods. The surface rupture strikes on average about N80°E sub-parallel to the main Altyn Tagh Fault, but is composed of several stepping segments with markedly different strike ranging from 68°N~87°E. The surface rupture is marked by pressure ridges, sub-fault strands, tension-gashes, pull-apart and faulted basins, likely caused by left-lateral strike-slip faulting. More than 30 pressure ridges can be distinguished with various rectangular, elliptical or elongated shapes. Most long axis of the ridges are oblique(90°N~140°E)to, but a few are nearly parallel to the surface rupture strike. The ridge sizes vary also, with heights from 1 to 15m, widths from several to 60m, and lengths from 10 to 100m. The overall size of these pressure ridges is similar to those found along the Altyn Tagh Fault, for instance, south of Pingding Shan or across Xorkol. Right-stepping 0.5~1m-deep gashes or sub-faults, with lengths from a few meters to several hundred meters, are distributed obliquely between ridges at an angle reaching 30°. The sub-faults are characterized with SE or NW facing 0.5~1m-high scarps. Several pull-apart and faulted basins are bounded by faults along the eastern part of the surface rupture. One large pull-apart basins are 6~7m deep and 400m wide. A faulted basin, 80m wide, 500m long and 3m deep, is bounded by 2 left-stepping left-lateral faults and 4 right-stepping normal faults. Two to three m-wide gashes are often seen on pressure ridges, and some ridges are left-laterally faulted and cut into several parts, probably owing to the occurrence of repetitive earthquakes. The OSL dating indicates that the most recent rupture might occur during Holocene.
Southwestwards the rupture trace disappears a few hundred meters north of a south dipping thrust scarp bounding uplifted and folded Plio-Quaternary sediments to the south. Thrust scarps can be followed southwestward for another 12km and suggest a connection with the south Pingding Shan Fault, a left-lateral splay of the main Altyn Tagh Fault. To the northeast the rupture trace progressively veers to the east and is seen cross-cutting the bajada south of Datonggou Nanshan and merging with active thrusts clearly outlined by south facing cumulative scarps across the fans. The geometry of this strike-slip fault trace and the clear young seismic geomorphology typifies the present and tectonically active link between left-lateral strike-slip faulting and thrusting along the eastern termination of the Altyn Tagh Fault, a process responsible for the growth of the Tibetan plateau at its northeastern margin. The discrete relation between thrusting and strike-slip faulting suggests discontinuous transfer of strain from strike-slip faulting to thrusting and thus stepwise northeastward slip-rate decrease along the Altyn Tagh Fault after each strike-slip/thrust junction. 相似文献
Southwestwards the rupture trace disappears a few hundred meters north of a south dipping thrust scarp bounding uplifted and folded Plio-Quaternary sediments to the south. Thrust scarps can be followed southwestward for another 12km and suggest a connection with the south Pingding Shan Fault, a left-lateral splay of the main Altyn Tagh Fault. To the northeast the rupture trace progressively veers to the east and is seen cross-cutting the bajada south of Datonggou Nanshan and merging with active thrusts clearly outlined by south facing cumulative scarps across the fans. The geometry of this strike-slip fault trace and the clear young seismic geomorphology typifies the present and tectonically active link between left-lateral strike-slip faulting and thrusting along the eastern termination of the Altyn Tagh Fault, a process responsible for the growth of the Tibetan plateau at its northeastern margin. The discrete relation between thrusting and strike-slip faulting suggests discontinuous transfer of strain from strike-slip faulting to thrusting and thus stepwise northeastward slip-rate decrease along the Altyn Tagh Fault after each strike-slip/thrust junction. 相似文献
15.
A PRELIMINARY RESEARCH ON THE RIGHT-LATERAL STRIKE-SLIP CHARACTERISTICS AND THE STRUCTURAL SIGNIFICANCE OF THE NORTHERN KUANTANSHAN FAULTS,HEXI CORRIDER,BASED ON HIGH-RESOLUTION IMAGERY 下载免费PDF全文
下载免费PDF全文 The sinistral strike-slip characteristic of the Altyn Tagh Fault gradually disappears near the Jiuxi Basin at the west end of Hexi Corridor, and the Kuantanshan Fault and the northern marginal fault of Heishan on its east are thrust structures. There are two faults distributed in the north of Kuantanshan, namely, the Taerwan-Chijiaciwo Fault and the Ganxiashan Fault, both are featured with obvious activity. Predecessors thought that the Taerwan-Chijiaciwo Fault is a thrust fault with low movement rate, but there is few detailed study on its horizontal motion. Is there horizontal strike-slip movement in the northern marginal fault of Kuantanshan? This issue has an important significance to further explore the structural transformation mode between the Altyn Tagh strike-slip faults and the northern thrust faults in the north margin of Qilianshan. Using high resolution remote sensing images and field work, such as combining with UAV SfM photogrammetry, the paper studies the strike-slip characteristics of the Taerwan-Chijiaciwo Fault and Ganxiashan Fault on the northern margin of Kuantanshan, and get two preliminary understandings:(1) The northern marginal fault of Kuantanshan is an active right-lateral strike-slip fault with thrust component, the horizontal to vertical dislocation ratio is about 3-4 times. Based on the statistics of dislocation amount of the gullies and terraces along the north marginal Kuantanshan fault, it is preliminarily estimated that the late Pleistocene right-lateral strike-slip rate is about 0.2-0.25 mm/a and the Holocene right-lateral strike-slip rate is about 0.5-1.5 mm/a. (2) The main driving force to the tectonics at the western end of Hexi Corridor, where the northern marginal fault of Kuantanshan locates, comes from the northward extrusion of the Qilian Mountains, which results in the right-lateral strike-slip of the northern marginal fault of Kuananshan and the thrust movement of several faults inside the Jiuxi Basin. The effect of the Altyn Tagh Fault on other tectonic structures is not obvious in this region. 相似文献
16.
青藏高原东北缘合作-大井剖面地壳电性结构研究 总被引：14，自引：8，他引：6
青藏高原东北缘合作-大井剖面的大地电磁探测结果表明,该区域的电性结构呈明显的纵向分层、横向分块的特点,中下地壳普遍存在高导层.青藏高原东北缘西秦岭北缘断裂带、北祁连南缘断裂带、北祁连北缘断裂带(海原断裂带)及龙首山南缘断裂带等区域性断裂带在电性结构模型中均表现为电性梯度带或低阻异常带.电性结构的横向分区与构造上的地块划分有明显的一致性,各个地块的电性结构存在明显差异.西秦岭北缘断裂带作是一个大型的板块边界,但板块结合带附近没有明显逆冲或俯冲痕迹,可能主要以左旋走滑为主.北祁连地块向北仰冲与阿拉善地块向南俯冲边界可能不是海原断裂带,而是龙首山南缘断裂带.西秦岭造山带内的壳内高导层与青藏高原内部存在的高导层具有可对比性,可能是由于部分熔融与含盐水流体共同作用的结果.中祁连地块内的高导层可能是含盐水流体引起的.而北祁连与河西走廊过渡带内的高导层则可能是板块俯冲或仰冲的构造运动痕迹,也可能是由含盐水流体引起的. 相似文献
17.
GEOLOGICAL AND GEOMORPHIC EXPRESSIONS OF LATE QUATERNARY STRIKE-SLIP ACTIVITY ON JINTA NANSHAN FAULT IN NORTHERN EDGE OF QING-ZANG BLOCK 下载免费PDF全文
下载免费PDF全文 Jinta Nanshan Fault is an important fault in northeast front of Qing-Zang Plateau, and it is crucial for determining the eastern end of Altyn Tagh Fault. However, there is still debate on its significant strike-slip movement.
In this paper, we study the Late Quaternary activity of Jinta Nanshan Fault and its geological and geomorphic expressions by interpreting aerial photographs and high-resolution remote sensing images, surveying and mapping of geological and geomorphic appearances, digging and clarifying fault profiles and mapping deformation characteristics of micro-topographies, then we analyze whether strike-slip activity exists on Jinta Nanshan Fault.
We get a more complete fault geometry than previous studies from most recent remote sensing images. Active fault traces of Jinta Nanshan mainly include 2 nearly parallel, striking 100°~90° fault scarps, and can be divided into 3 segments. West segment and middle segment form a left stepover with 2~2.5km width, and another stepover with 1.2km width separates the middle and east segment.
We summarize geomorphic and geologic evidence relating to strike slip activity of Jinta Nanshan Fault. Geomorphic expressions are as follows:First, fault scarps with alternating facing directions; second, sinistral offset of stream channels and micro-topographies; third, pull-apart basins and compressive-ridges at discontinuous part of Jinta Nanshan Fault. Geologic expressions are as follows:First, fault plane characteristics, including extremely high fault plane angle, unstable dip directions and coexistence of normal fault and reverse fault; second, flower structures.
Strike-slip rate was estimated by using geomorphic surface age of Zheng et al.(2013)and left-lateral offset with differential GPS measurements of the same geomorphic surface at field site in Fig. 4e. We calculated a strike-slip rate of (0.19±0.05)mm/a, which is slightly larger than or almost the same with vertical slip rate of (0.11±0.03)mm/a from Zheng et al.(2013).
When we confirm the strike-slip activity of Jinta Nanshan, we discuss its potential dynamic sources:First, eastern extension of Altyn Tagh Fault and second, strain partitioning of northeastward extension of Qilian Shan thrust belt. The first one is explainable when it came to geometric pattern of several E-W striking fault and eastward decreasing strike slip rate, but the former cannot explain why the Heishan Fault, which locates between the the Altyn Tagh Fault and Jinta Nanshan Fault, is a pure high angle reverse fault. The latter seems more explainable, because oblique vectors may indeed partition onto a fault and manifest strike-slip activity. 相似文献
18.
Constant slip rate during the late Quaternary along the Sulu He segment of the Altyn Tagh Fault near Changma,Gansu, China 总被引：1，自引：0，他引：1
The question of whether millennial‐scale geological slip rates are consistent with decade‐scale geodetic slip rates is of great importance in evaluating the nature of continental deformation within the Tibetan Plateau. We determined the time‐averaged slip rate of the Sulu He segment of the Altyn Tagh Fault, near Changma in Gansu Province, China, based on geomorphic analysis, remote sensing data, and cosmogenic 10Be surface‐exposure age dating. Quaternary alluvial fan deposits in the study area (Qf1, Qf2, Qf3) are displaced by left‐lateral movement along the Altyn Tagh Fault. Because of the large accumulated displacement of these fans, some of them have become disconnected from the fan apexes that are directly linked to the debris‐source areas in the piedmont of the Qilian Shan to the south. The total minimum offsets are estimated to be about 429 ± 41 m for Qf1, about 130 ± 10 m for Qf2, and 32 ± 1 m for Qf3. The 10Be surface‐exposure ages obtained for Qf1 and Qf2 are 100–112 ka and 31–43 ka, respectively. Accordingly, the slip rate since the period of Qf1 and Qf2 depositions is calculated to have been about 3.7 mm/yr. 相似文献
19.
《Earth and Planetary Science Letters》2006,241(3-4):804-814
We present new seismic refraction/wide-angle-reflection data across the Altyn Tagh Range and its adjacent basins. We find that the crustal velocity structure, and by inference, the composition of the crust changes abruptly beneath the Cherchen fault, i.e., ∼100 km north of the northern margin of the Tibetan plateau. North of the Cherchen fault, beneath the Tarim basin, a platform-type crust is evident. In contrast, south the Cherchen fault the crust is characterized by a missing high-velocity lower-crustal layer. Our seismic model indicates that the high topography (∼3 km) of the Altyn Tagh Range is supported by a wedge-shaped region with a seismic velocity of 7.6–7.8 km/s that we interpret as a zone of crust–mantle mix. We infer that the Altyn Tagh Range formed by crustal-scale strike-slip motion along the North Altyn Tagh fault and northeast–southwest contraction over the range. The contraction is accommodated by (1) crustal thickening via upper-crustal thrusting and lower-crustal flow (i.e., creep), and (2) slip-parallel (SW-directed) underthrusting of only the lower crust and mantle of the eastern Tarim basin beneath the Altyn Tagh Range. 相似文献