P-T evolution of glaucophane-omphacite bearing HP-LT rocks in the western Tianshan Orogen, NW China: new evidence for 'Alpine-type' tectonics
文献类型:期刊论文
作者 | Klemd, R; Schroter, FC; Will, TM; Gao, J |
刊名 | JOURNAL OF METAMORPHIC GEOLOGY
![]() |
出版日期 | 2002-02-01 |
卷号 | 20期号:2页码:239-254 |
关键词 | 'Alpine-type' tectonics blueschist eclogite P-T path P-T-pseudosections western Tianshan |
ISSN号 | 0263-4929 |
文献子类 | Article |
英文摘要 | The late Palaeozoic western Tianshan high-pressure/low-temperature belt extends for about 200 km along the south-central Tianshan suture zone and is composed mainly of blueschist, eclogite and epidote amphibolite/greenschist facies rocks. P-T conditions of mafic garnet omphacite and garnet-omphacite blueschist, which are interlayered with eclogite, were investigated in order to establish an exhumation path for these high-pressure rocks. Maximum pressure conditions are represented by the assemblage garnet-omphacite-paragonite-phengite-glaucophane-quartz-rutile. Estimated maximum pressures range between 18 and 21 kbar at temperatures between 490 and 570 degreesC. Decompression caused the destabilization of omphacite, garnet and glaucophane to albite, Ca-amphibole and chlorite. The post-eclogite facies metamorphic conditions between 9 and 14 kbar at 480 570 degreesC suggest an almost isothermal decompression from eclogite to epidote-amphibolite facies conditions. Prograde growth zoning and mineral inclusions in garnet as well as post-eclogite facies conditions are evidence for a clockwise P-T path. Analysis of phase diagrams constrains the P-T path to more or less isothermal cooling which is well corroborated by the results of geothermobarometry and mineral textures. This implies that the high-pressure rocks from the western Tianshan Orogen formed in a tectonic regime similar to 'Alpine-type' tectonics. This contradicts previous models which favour 'Franciscan-type' tectonics for the southern Tianshan high-pressure rocks. |
WOS关键词 | HIGH-PRESSURE METAMORPHISM ; TEMPERATURE TIME PATHS ; REGIONAL METAMORPHISM ; NORTHWESTERN CHINA ; PHASE-RELATIONS ; BLUESCHIST ; PLAGIOCLASE ; THERMOBAROMETRY ; TRANSFORMATION ; NOMENCLATURE |
WOS研究方向 | Geology |
语种 | 英语 |
WOS记录号 | WOS:000174028500002 |
出版者 | WILEY-BLACKWELL |
源URL | [http://ir.iggcas.ac.cn/handle/132A11/77421] ![]() |
专题 | 中国科学院地质与地球物理研究所 |
通讯作者 | Klemd, R |
作者单位 | 1.Univ Wurzburg, Inst Mineral, D-97074 Wurzburg, Germany 2.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China |
推荐引用方式 GB/T 7714 | Klemd, R,Schroter, FC,Will, TM,et al. P-T evolution of glaucophane-omphacite bearing HP-LT rocks in the western Tianshan Orogen, NW China: new evidence for 'Alpine-type' tectonics[J]. JOURNAL OF METAMORPHIC GEOLOGY,2002,20(2):239-254. |
APA | Klemd, R,Schroter, FC,Will, TM,&Gao, J.(2002).P-T evolution of glaucophane-omphacite bearing HP-LT rocks in the western Tianshan Orogen, NW China: new evidence for 'Alpine-type' tectonics.JOURNAL OF METAMORPHIC GEOLOGY,20(2),239-254. |
MLA | Klemd, R,et al."P-T evolution of glaucophane-omphacite bearing HP-LT rocks in the western Tianshan Orogen, NW China: new evidence for 'Alpine-type' tectonics".JOURNAL OF METAMORPHIC GEOLOGY 20.2(2002):239-254. |
入库方式: OAI收割
来源:地质与地球物理研究所
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。