Dolomite dissociation indicates ultra-deep (> 150 km) subduction of a garnet-bearing dunite block (the Sulu UHP terrane)

doi:10.2138/am-2017-5982

CORC > 地质与地球物理研究所 > 中国科学院地质与地球物理研究所 > 岩石圈演化国家重点实验室

	Dolomite dissociation indicates ultra-deep (> 150 km) subduction of a garnet-bearing dunite block (the Sulu UHP terrane)
	Su, Bin 1,3; Chen, Yi 1,2; Guo, Shun 1,2; Liu, Jing-Bo 1
刊名	AMERICAN MINERALOGIST
	2017-11-01
卷号	102 期号:11 页码:2295-2306
关键词	Dunite Dolomite Dissociation Ultra-deep Subduction Sulu Belt
ISSN号	0003-004X
DOI	10.2138/am-2017-5982
文献子类	Article
英文摘要	The dissociation of dolomite into magnesite and aragonite has been regarded as a useful indicator for ultrahigh-pressure (UHP) metamorphism. In this study we investigate an unusual texture involving magnesite and calcite intergrowths with dolomite relicts in a garnet-bearing dunite block from the Sulu UHP terrane, eastern China. The carbonate intergrowths typically occur as interstitial grains with low dihedral angles against surrounding olivines and have a dolomitic precursor composition. Our observations indicate that the carbonate intergrowths were initially inherited from the well-documented magnesite and aragonite assemblage after dolomite dissociation. The initial dolomite grains were likely to crystallize during the dolomitic melt metasomatism within the shallow lithospheric mantle. A series of experimental studies have well determined the equilibrium boundary of dolomite = magnesite + aragonite greater than 5 GPa along a wide temperature range, which provides direct evidence that the dunite block was subducted to depths greater than 150 km during the Triassic continental subduction. The preservation of magnesite and aragonite (now calcite) intergrowths without dolomite synthesis reaction during exhumation is probably due to the lack of fluid and rapid decompression from the peak stage to the calcite stability field. In this study, we suggest that dunite blocks from high-pressure and UHP terranes could have subducted to UHP conditions similar to garnet lherzolite and pyroxenite and were then entrained into slab slices rapidly en route to the surface.
WOS关键词	ARAGONITE PLUS MAGNESITE ; FINERO PHLOGOPITE-PERIDOTITE ; WESTERN GNEISS REGION ; EASTERN CHINA ; HIGH-PRESSURE ; CONTINENTAL SUBDUCTION ; LITHOSPHERIC MANTLE ; TRACE-ELEMENT ; CENTRAL ALPS ; MULTISTAGE METAMORPHISM
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	MINERALOGICAL SOC AMER
WOS记录号	WOS:000414669300014
资助机构	National Basic Research Program of China (973 Program)(2015CB856103) ; National Basic Research Program of China (973 Program)(2015CB856103) ; National Science Foundation of China(41372078 ; National Science Foundation of China(41372078 ; National Postdoctoral Program for Innovative Talents(BX201700239) ; National Postdoctoral Program for Innovative Talents(BX201700239) ; 41372080) ; 41372080) ; National Basic Research Program of China (973 Program)(2015CB856103) ; National Basic Research Program of China (973 Program)(2015CB856103) ; National Science Foundation of China(41372078 ; National Science Foundation of China(41372078 ; National Postdoctoral Program for Innovative Talents(BX201700239) ; National Postdoctoral Program for Innovative Talents(BX201700239) ; 41372080) ; 41372080) ; National Basic Research Program of China (973 Program)(2015CB856103) ; National Basic Research Program of China (973 Program)(2015CB856103) ; National Science Foundation of China(41372078 ; National Science Foundation of China(41372078 ; National Postdoctoral Program for Innovative Talents(BX201700239) ; National Postdoctoral Program for Innovative Talents(BX201700239) ; 41372080) ; 41372080) ; National Basic Research Program of China (973 Program)(2015CB856103) ; National Basic Research Program of China (973 Program)(2015CB856103) ; National Science Foundation of China(41372078 ; National Science Foundation of China(41372078 ; National Postdoctoral Program for Innovative Talents(BX201700239) ; National Postdoctoral Program for Innovative Talents(BX201700239) ; 41372080) ; 41372080)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/62484]
专题	地质与地球物理研究所_岩石圈演化国家重点实验室
通讯作者	Chen, Yi
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, POB 9825, Beijing 100029, Peoples R China 2.CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China 3.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Su, Bin,Chen, Yi,Guo, Shun,et al. Dolomite dissociation indicates ultra-deep (> 150 km) subduction of a garnet-bearing dunite block (the Sulu UHP terrane)[J]. AMERICAN MINERALOGIST,2017,102(11):2295-2306.
APA	Su, Bin,Chen, Yi,Guo, Shun,&Liu, Jing-Bo.(2017).Dolomite dissociation indicates ultra-deep (> 150 km) subduction of a garnet-bearing dunite block (the Sulu UHP terrane).AMERICAN MINERALOGIST,102(11),2295-2306.
MLA	Su, Bin,et al."Dolomite dissociation indicates ultra-deep (> 150 km) subduction of a garnet-bearing dunite block (the Sulu UHP terrane)".AMERICAN MINERALOGIST 102.11(2017):2295-2306.