西南天山明尧勒背斜的第四纪滑脱褶皱作用   总被引：3，自引：1，他引：3       下载免费PDF全文

陈杰  Scharer K M  Burbank D W  Heermance R  王昌盛 《地震地质》2005,27(4):530-547

通过对明尧勒活动背斜喀浪勾律克河剖面生长前地层和翼部生长地层几何结构的填图以及变形河流阶地的系统测量,结合磁性地层及释光年代学研究,认为该背斜的滑脱褶皱作用起始于距今约1·6Ma,其总体几何结构形成于褶皱作用的早期,但其生长扩展并不完全遵从自相似性特征。持续的缩短作用部分被褶皱翼部陡倾膝折带的加长所吸收(由此导致背斜波幅的增加),另一部分可能是通过不同时期褶皱翼部不同膝折带组的旋转和迁移来实现的。明尧勒背斜的持续构造抬升是背斜区河流下切形成多级基座阶地的主因。晚第四纪褶皱的生长以背斜的垂直抬升为主,主要集中在北翼近核部,背斜宽度变化不大。背斜不同时期的抬升量和抬升速率均大于其缩短量和缩短速率,表明明尧勒背斜的变形以翼旋转为主(Pobletet al.,1996)。背斜自形成以来缩短速率和抬升速率均有减小的趋势  相似文献   

Dislocation structure of the crust-mantle boundary and low-velocity body within the crust beneath the Dabie Shan collision orogen     

LIU Qiyuan  Rainer Kind  CHEN Jiuhui  YUAN Xiaohui  LI Shuncheng  GUO Biao  Kurt Wylegalla & LAI Yuangen . State Key Laboratory of Earthquake Dynamics  Institute of Geology  China Earthquake Administration  Beijing  China  . GeoForschungZentrum Potsdam  Telegrafenburg A  Potsdam  D-  Germany 《中国科学D辑(英文版)》2005,48(7)

The Dabie Shan is located on the eastern side of the Qinling-Dabie orogenic belt, which marks a geological boundary between the Sino-Korean and Yangtze cra- ton. Since the 1980s, the discovery of coesite and mi- crodiamond in the Dabie Shan orogen motivates an extensive interest to the ultra-high pressure (UHP)metamorphism and its exhumation[1,2]. Many results about them were published, which deal with different disciplines, including tectonics, petrology and chro- nology[3?8]. Up to now,…  相似文献   

Metamorphic zircon from Xindian eclogite,Dabie Terrain: U-Pb age and oxygen isotope composition   总被引：2，自引：1，他引：2  

E. Deloule 《中国科学D辑(英文版)》2006,49(1):68-76

~~Metamorphic zircon from Xindian eclogite,Dabie Terrain: U-Pb age and oxygen isotope composition@E. Deloule$CRPG-CNRS Nancy,54501,France1. Vavra, G, Gebauer. D., Schmid. R. et al., Multiple zircon growth and recrystallization during polyphase Late Carboniferous to Tri-assic metamorphism in granulites of the Ivrea Zone (Southern Alps): an ion microprobe (SHRIMP) study, Contrib. Mineral Petrol., 1996, 122:337-358 2. Vavra, G, Schmid, R., Gebauer, D., Internal morphology, ha…  相似文献   

Extremely large rockslides and rock avalanches in the Tien Shan Mountains, Kyrgyzstan     

Alexander L. Strom  Oliver Korup 《Landslides》2006,3(2):125-136

Most systematic research on large rock-slope failures is geographically biased towards reports from Europe, the Americas, the Himalayas and China. Although reports exist on large rockslides and rock avalanches in the territory of the former Soviet Union, they are not readily available, and few translations have been made. To begin closing this gap, we describe here preliminary data from field reconnaissance, remote sensing and geomorphometry of nine extremely large rock-slope failures in the Tien Shan Mountains of central Kyrgyzstan. Each of these catastrophic and prehistoric failures exceeds an estimated 1 km³ in volume, and two of them involve about 10 km³. Failure of rock slopes in wide valleys favoured the emplacement of hummocky long-runout deposits, often spreading out over >10 km², blocking major rivers. Most of these gigantic slope failures are located on or near active faults. Their spatial clustering and the high seismic activity in the Tien Shan support the hypothesis that strong seismic shaking caused or triggered most of these large-scale rock-slope failures. Nevertheless detailed field studies and laboratory analyses will be necessary to exclude hydroclimatic trigger mechanisms (precipitation, fluvial undercutting, permafrost degradation), and to determine their absolute ages, frequency and the large-landslide hazard of central Kyrgyzstan.  相似文献   

大别山东部超高太变质带北侧的花岗片麻岩及其构造背景   总被引：1，自引：0，他引：1  

吴维平  徐树桐  江来利  刘贻灿  苏文  石永红  范高红  陈金苗  沈欢喜 《安徽地质》1998,(1)

大别山东部超高压变质带北侧的花岗片麻岩有下列特征。（１）化学成分富硅、富碱,一般ＳｉＯ２＜７５％,Ｋ２Ｏ＋Ｎａ２Ｏ＞８％,且Ｋ２Ｏ＞Ｎａ２Ｏ。（２）与变质表壳岩有侵入接触关系,有异源、深源包体。（３）主要为鳞片花岗变晶结构,有残留的岩浆结构,普遍具片麻状构造,钾长石常以眼球状巨晶出现,剪切带中发育Ｌ＞Ｓ型变形组构。（４）变质作用为角闪岩相,变质矿物为黑云母、角闪石以及少量石榴石、白云母、绿帘石等。。（５）锆石的乙—Ｐ６同位素年龄值为６２９Ｍａ。上述特征与超高压变质带中的含霓石变质花岗岩有明显的区别,因此,它可能是杨子大陆板块的俯冲基底。  相似文献   

Development of Tectonic Geomorphology Study Promoted by New Methods in China: A Viewpoint from Reviewing the Tian Shan Researches     

Lü Honghua  Youli Li 《地球科学进展》1986,35(6):594-606

Tectonic Geomorphology is an important branch of Geomorphology. Now the scope of tectonic geomorphology study has covered the interactions between tectonics, climate, surface processes and the influence on geomorphic evolution. The study of tectonic geomorphology in China started at the beginning of the 20th century, developed gradually in the 1950s, and entered a rapid development stage in the new century. Based on the long-term development, the study of tectonic geomorphology in China has formed a relatively complete theoretical and methodological system, and now presents a trend of the continuous intersection and integration with other adjacent disciplines. Now, several books on tectonic geomorphology have been published. The representative book abroad is Tectonic Geomorphology which was edited by Burbank D. W. and Anderson R. S., and was first published in 2001 and reprinted in 2012. In China, the first book on tectonic geomorphology is Active Tectonic Geomorphology which was edited by Yang Jingchun and Li Youli and was first published in 2011.In recent years, the tectonic geomorphology study has been absorbing and integrating the new ideas and new methods of other disciplines, significantly promoting the development of tectonic geomorphology. At the 2019 China Geographic Congress & the 110th anniversary of the establishment of the Chinese Geographical Society, the authors organized the session "Theory, Method and Application of Tectonic Geomorphology", aiming to present the recent progresses of tectonic geomorphology study in China. Later, invited by the editorial office, the authors organized the special column with the same name in the journal Advances in Earth Science. The contents of this column mainly dealt with the classical theoretical problems of geomorphology (the evolution and the controlling mechanism of river terrace, planation surface, and alluvial fan), new methods (such as K-feldspar thermoluminescence thermochronology, detrital zircon U-Pb chronology), and models and numerical simulation of tectonic geomorphology evolution. Because of the limited number of the articles, it was impossible for this column to comprehensively present the recent progresses in the study of tectonic geomorphology in China. Therefore, this paper first briefly reviewed the history of the development of tectonic geomorphology in China and the basic trend of tectonic geomorphology. The authors started the study of neotectonics and tectonic geomorphology in the Tian Shan range and its foreland basins about 15 years ago (exactly in 2002). The main aim of this paper was to explore the contributions of the interdisciplinary and new methods to the development of tectonic geomorphology study, by reviewing the main achievements in the tectonic geomorphology study conducted in the Tian Shan and its foreland basins during the past 20 years. These achievements include the history of uplift and exhumation during the Cenozoic times, the chronology and genesis of the late Cenozoic terrigenous sedimentary sequences in the foreland basins, the characteristics of the late Quaternary active tectonic deformation in the foreland and intermontane basins, the late Quaternary river geomorphology (geomorphic framework, chronology, and cause of formation), and erosion rates of the catchment basins. At the end of this paper, it was pointed out that, two aspects may need more attention in the future tectonic geomorphology study, i.e. the comparative study at different time scales and the better constraint of the formation age of river terrace.  相似文献   

Multiple generations of pseudotachylyte in the brittle to ductile regimes, Qinling–Dabie Shan ultrahigh-pressure metamorphic complex, central China     

Aiming Lin  Zhiming Sun  Zhenyu Yang 《Island Arc》2003,12(4):423-435

Abstract Pseudotachylytes are present along the Dahezhen shear zone in the Qinling–Dabie Shan collisional orogenic belt, central China. Two types of pseudotachylyte vein are documented in the shear zone: cataclasite‐related pseudotachylyte (C‐Pt) and mylonite‐related pseudotachylyte (M‐Pt). M‐Pt is associated with mylonite‐development and is overprinted by C‐Pt. All of the quartz and most of the feldspar porphyroclasts within the M‐Pt are plastically deformed, but not in the C‐Pt. Dynamically recrystallized fine‐grained quartz and feldspar bands are oriented subparallel to the mylonite and M‐Pt foliation, and partially surround the porphyroclasts. Our results suggest that the M‐Pt formed cyclically in the ductile region at estimated conditions of 400–650°C and 400–800 MPa due to propagation of seismic fracturing associated with the thrusting‐related rapid exhumation of the ultrahigh‐pressure metamorphic complex in the brittle regime down to a greater depth than the base of the seismogenic zone. The M‐Pt and mylonite formed in the Dahezhen shear zone at estimated conditions of 400–650°C and 400–800 MPa. The coexistence of C‐Pt and M‐Pt in the same shear zone suggests that repeated seismic slips occurred in both the brittle and ductile portions of the crust during the thrusting‐related rapid exhumation of the ultrahigh‐pressure metamorphic complex.  相似文献   

中国新疆天山博阿断裂晚第四纪右旋走滑运动特征   总被引：13，自引：3，他引：13       下载免费PDF全文

沈军  汪一鹏  李莹甄  姜慧  向志勇 《地震地质》2003,25(2):183-194,T001

利用遥感资料 ,通过野外实地考察并结合气候地貌事件的分析 ,对斜切北天山、长逾70 0km的博阿断裂 (博罗科努 -阿齐克库都克断裂 )的右旋走滑运动进行了定量研究。该断裂分为西部NW向断裂和东部NWW向断裂。西部NW向断裂长近 2 5 0km ,向西北延伸进入哈萨克斯坦 ,右旋走滑速率可达 5mm/a ;由 4～ 5个断裂段组成 ,其上发育 3～ 4条古地震或历史地震形变带 ,显示具有发生 7.5级地震的能力。东部NWW向断裂右旋走滑速率 1～ 1.4mm/a ;其上发现小规模古地震形变带 ,显示具备发生 7级左右地震的能力。该断裂与山前的逆冲推覆构造之间构成典型的挤压区应变分配形式 ,即在斜向挤压作用下 ,变形分配为山前的逆冲推覆构造和山内的走滑断裂  相似文献   

Intraplate mountain building in response to continent–continent collision—the Ancestral Rocky Mountains (North America) and inferences drawn from the Tien Shan (Central Asia)     

Patricia Wood Dickerson   《Tectonophysics》2003,365(1-4):129

The intraplate Ancestral Rocky Mountains of western North America extend from British Columbia, Canada, to Chihuahua, Mexico, and formed during Early Carboniferous through Early Permian time in response to continent–continent collision of Laurentia with Gondwana—the conjoined masses of Africa and South America, including Yucatán and Florida. Uplifts and flanking basins also formed within the Laurentian Midcontinent. On the Gondwanan continent, well inboard from the marginal fold belts, a counterpart structural array developed during the same period. Intraplate deformation began when full collisional plate coupling had been achieved along the continental margin; the intervening ocean had been closed and subduction had ceased—that is, the distinction between upper versus lower plates became moot. Ancestral Rockies deformation was not accompanied by volcanism. Basement shear zones that formed during Mesoproterozoic rifting of Laurentia were reactivated and exerted significant control on the locations, orientations, and modes of displacement on late Paleozoic faults.Ancestral Rocky Mountain uplifts extend as far south as Chihuahua and west Texas (28° to 33°N, 102° to 109°W) and include the Florida-Moyotes, Placer de Guadalupe–Carrizalillo, Ojinaga–Tascotal and Hueco Mountain blocks, as well as the Diablo and Central Basin Platforms. All are cored with Laurentian Proterozoic crystalline basement rocks and host correlative Paleozoic stratigraphic successions. Pre-late Paleozoic deformational, thermal, and metamorphic histories are similar as well. Southern Ancestral Rocky Mountain structures terminate along a line that trends approximately N 40°E (present coordinates), a common orientation for Mesoproterozoic extensional structures throughout southern to central North America.Continuing Tien Shan intraplate deformation (Central Asia) has created an analogous array of uplifts and basins in response to the collision of India with Eurasia, beginning in late Miocene time when full coupling of the colliding plates had occurred. As in the Laurentia–Gondwana case, structures of similar magnitude and spacing to those in Eurasia have developed in the Indian plate. Within the present orogen two ancient suture zones have been reactivated—the early Paleozoic Terskey zone and the late Paleozoic Turkestan suture between the Siberian and East Gondwanan cratons. Inverted Proterozoic to early Paleozoic rift structures and passive-margin deposits are exposed north of the Terskey zone. In the Alay and Tarim complexes, Vendian to mid-Carboniferous passive-margin strata and the subjacent Proterozoic crystalline basement have been uplifted. Data on Tien Shan uplifts, basins, structural arrays, and deformation rates guide paleotectonic interpretations of ancient intraplate mountain belts. Similarly, exhumed deep crustal shear zones in the Ancestral Rockies offer insight into partitioning and reorientation of strain during contemporary intraplate deformation.  相似文献   

Quaternary folding of the eastern Tian Shan, northwest China   总被引：3，自引：0，他引：3  

Bihong Fu  Aiming Lin  Ken-ichi Kano  Tadashi Maruyama  Jianming Guo 《Tectonophysics》2003,369(1-2):79-101

The Tian Shan, east–west trending more than 2000 km, is one of most active intracontinental mountain building belts that resulted from India–Eurasia collision during Cenozoic. In this study, Quaternary folding related to intracontinental mountain building of the Tian Shan orogenic belt is documented based on geologic interpretation and analyses of the satellite remote sensing images [Landsat Thematic Mapper (TM)/Enhanced Thematic Mapper (ETM) and India Remote Sensing (IRS) Pan] combined with field geologic and geomorphic observations and seismic reflection profiles. Analyses of spatial–temporal features of Quaternary folded structure indicate that the early Quaternary folds are widely distributed in both piedmont and intermontane basins, whereas the late Quaternary active folds are mainly concentrated on the northern range-fronts. Field observations indicate that Quaternary folds are mainly characterized by fault-related folding. The formation and migration of Quaternary folding are likely related to decollement surfaces beneath the fold-and-fault zone as revealed by seismic reflection profiles. Moreover, analysis of growth strata indicates that the Quaternary folding began in late stage of early Pleistocene (2.1–1.2 Ma). Finally, tectonic evolution model of the Quaternary deformation in the Tian Shan is presented. This model shows that the Quaternary folding and faulting gradually migrate toward the range-fronts due to the continuous compression related to India–Eurasia collision during Quaternary time. As a result, the high topographic relief of the Tian Shan was formed.  相似文献