Mineral inclusions in zircons of para- and orthogneiss from pre-pilot;drillhole CCSD-PP1, Chinese Continental Scientific Drilling Project

doi:10.1016/S0024-4937(01)00064-0

	Mineral inclusions in zircons of para- and orthogneiss from pre-pilot;drillhole CCSD-PP1, Chinese Continental Scientific Drilling Project
	Liu, FK 4; Xua, ZQ ; Katayama, I ; Yang, JS ; Maruyama, S ; Liou, JG
刊名	LITHOS
	2001
卷号	59 期号:4 页码:199-215
关键词	mineral inclusions zircons paragneiss orthogneiss pre-pilot drillhole CCSD-PP1
ISSN号	0024-4937
DOI	10.1016/S0024-4937(01)00064-0
英文摘要	The pre-pilot drillhole CCSD-PP1, Chinese Continental Scientific Drilling Project (CCSD), with depth of 432 m, is located in the Donghai area in the southwestern Sulu terrane. The core samples are mainly comprised of paragneiss, orthogneiss and ultrainafic rock with minor intercalated layers of eclogite and phengite-bearing kyanite quartzite. All analyzed paragneiss and orthogneiss samples were overprinted on amphibolite facies retrograde metamorphism. Coesite and coesite-bearing ultrahigh-pressure (UHP) mineral assemblages were identified by Raman spectroscopy and electron microprobe analysis as inclusions in zircons separated from paragneiss, eclogite and phengite-bearing kyanite quartzite samples. In the paragneiss samples, UHP mineral inclusion assemblages mainly consist of Coe + Omp + Grt + Phe, Coe + Jd + Phe + Ap preserved in the mantles (M) and rims (R) of zircons. These UHP mineral inclusion assemblages yield temperatures of 814-852 degreesC and pressures of greater than or equal to 28 kbar, presenting the P-T condition of UHP peak metamorphism of these country rocks. According to the mineral inclusions and cathodoluminescence images of zircons, the orthogneisses can be divided into two types: UHP (OG I) and non-UHP (OG2). In OG1 orthogneisses, low-pressure mineral inclusion assemblage, mainly consisting of Qtz+Phe+Ab+Ksp+Ap, were identified in zircon cores (C), while coesite or coesite-bearing UHP mineral inclusions were identified in the mantles (M) and rims (R) of the same zircons, These features suggest that the OG1 orthogneisses, together with the paragneisses, phengite-bearing kyanite quartzite and eclogite experienced widespread UHP metamorphism in the Sulu terrane. However, in the zircons of OG2 orthogneiss samples, no UHP mineral inclusions were found. Inclusions mainly comprised Qtz + Phe + Ap and were identified in cores (C), mantles (M) and rims (R) of OG2 zircons; the cathdoluminescence images of all analyzed zircons showed clear zonings from cores to rims. These features indicate that the OG2 orthogneisses in pre-pilot drillhole CCSD-PP I did not experience UHP metamorphism. Therefore, we should not rule out the possibility that some orthogneisses in Sulu terrane might represent relatively low-pressure granitic intrusives emplaced after the UHP event. (C) 2001 Elsevier Science B.V. All rights reserved.
学科主题	变质岩岩石学
WOS关键词	ULTRAHIGH-PRESSURE METAMORPHISM ; EASTERN CHINA ; DABIE MOUNTAINS ; TECTONIC IMPLICATIONS ; GARNET PERIDOTITES ; COUNTRY ROCKS ; COESITE ; TERRANE ; ECLOGITES ; PETROLOGY
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000172826600003
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/37450]
专题	中国地质科学院地质研究所
作者单位	1.China Acad Geol Sci, Inst Geol, Beijing 100037, Peoples R China. 2.Tokyo Inst Technol, Dept Earth & Planetary Sci, Tokyo 1528551, Japan. 3.Stanford Univ, Dept Geol Environm Sci, Stanford, CA 94305 USA. 4.中国地质科学院地质研究所
推荐引用方式 GB/T 7714	Liu, FK,Xua, ZQ,Katayama, I,et al. Mineral inclusions in zircons of para- and orthogneiss from pre-pilot;drillhole CCSD-PP1, Chinese Continental Scientific Drilling Project[J]. LITHOS,2001,59(4):199-215.
APA	Liu, FK,Xua, ZQ,Katayama, I,Yang, JS,Maruyama, S,&Liou, JG.(2001).Mineral inclusions in zircons of para- and orthogneiss from pre-pilot;drillhole CCSD-PP1, Chinese Continental Scientific Drilling Project.LITHOS,59(4),199-215.
MLA	Liu, FK,et al."Mineral inclusions in zircons of para- and orthogneiss from pre-pilot;drillhole CCSD-PP1, Chinese Continental Scientific Drilling Project".LITHOS 59.4(2001):199-215.