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DOI	10.1007/s11434-010-4127-y
	Finding of high-pressure mafic granulites in the Amdo basement, central Tibet
	Zhang XiaoRan; Shi RenDeng; Huang QiShuai; Liu DeLiang; Cidan SuoLang; Yang JingSui; Ding Lin
通讯作者	Shi, RD (通讯作者)
发表日期	2010
ISSN	1001-6538
EISSN	1861-9541
起始页码	3694
结束页码	3702
卷号	55 期号:32
英文摘要	High-pressure mafic granulites with a peak mineral assemblage of garnet + clinopyroxene + rutile + quartz were found in the Amdo basement, central Tibet. Two kinds of symplectites were identified that are composed of orthopyroxene + plagioclase +/- spinel and hornblende + plagioclase around garnet, which were interpreted to develop during the retrogressing stages in the granulites. P-T estimates suggested that peak metamorphic conditions were about 860-920 degrees C and 1.46-1.56 GPa, which retrogressed from post-peak phase at 820-890 degrees C and 0.88-1.15 GPa to amphibolite facies at 550-670 degrees C and 0.52-0.65 GPa. These three stages define a clockwise P-T path with near-isothermal decompression and cooling following the peak high-pressure metamorphism. This suggests that the Amdo granulites underwent an initial subduction to a deep crustal level of similar to 50 km and then were rapidly exhumed to a shallow crustal level (similar to 20 km). The formation of Amdo granulites is considered to result from the arc-continent collision between the Amdo basement and the Qiangtang terrane in the middle Jurassic, which is a crucial step to the tectonic evolution of the Tibetan Plateau.
关键词	P-T CONDITIONS DECOMPRESSION REACTIONS TECTONIC EVOLUTION DONQIAO OPHIOLITE CENTRAL QIANGTANG PLATE-TECTONICS LHASA GEOTRAVERSE ECLOGITES ROCKS
英文关键词	high-pressure granulite; P-T path; Amdo basement; Bangong-Nujiang Suture; Tibet
语种	英语
WOS研究方向	Science & Technology - Other Topics
WOS类目	Multidisciplinary Sciences
WOS记录号	WOS:000285026300011
来源期刊	CHINESE SCIENCE BULLETIN
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/257785
推荐引用方式 GB/T 7714	Zhang XiaoRan,Shi RenDeng,Huang QiShuai,et al. Finding of high-pressure mafic granulites in the Amdo basement, central Tibet[J]. 中国科学院青藏高原研究所,2010,55(32).
APA	Zhang XiaoRan.,Shi RenDeng.,Huang QiShuai.,Liu DeLiang.,Cidan SuoLang.,...&Ding Lin.(2010).Finding of high-pressure mafic granulites in the Amdo basement, central Tibet.CHINESE SCIENCE BULLETIN,55(32).
MLA	Zhang XiaoRan,et al."Finding of high-pressure mafic granulites in the Amdo basement, central Tibet".CHINESE SCIENCE BULLETIN 55.32(2010).