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DOI	10.18654/1000-0569/2020.04.11
	Discovery and genesis of two types of olivines and its significance to metallogeny in Jinchuan magmatic copper-nickel (PGE) sulfide deposit
	Liu MeiYu; Su ShangGuo; Yao Yuan; Wu XiaoMan; Cai Nan; Guan QiuYun
通讯作者	Su, SG (通讯作者)
发表日期	2020
ISSN	1000-0569
EISSN	2095-8927
起始页码	1151
结束页码	+
卷号	36 期号:4
英文摘要	The Jinchuan deposit is the third largest magmatic copper-nickel sulfide deposit in the world. There are still a lot of controversies about its metallogenic mechanism of which two main models can be summarized from former researches: (1) the magmatic conduit accumulation metallogenic model; and (2) the deep segregation -injection metallogenenic model. However, none of them can explain the geological phenomena in the mining area well. This paper focuses on the characteristics of olivines in the deposit to discuss the migration mode and emplacement ability of the sulfide melts. In this study, two types of olivines were found in the Jinchuan deposit, namely the LREE-depleted (type I) and the LREE-enriched (type II). The type I olivine is the primary minerals generated by crystallization of the ultramafic-mafic magma, which is widely distributed in various types of ultramafic rocks and sulfide ores in the deposit. It always occurred as complex composition bands formed by compositional changes between primary olivine and interstitial silicate/immiscible sulfide melt. This type of olivine inherited the low rare earth element (REE) contents of basaltic parent magma. The type II olivine is formed by recrystallization of cumulate orthopyroxene after its incongruent melting by a fluid -triggered process, which is mostly found in sulfide ores, always wrapped by orthopyroxene. It has high REE content (about 2 orders of magnitude higher than that of the type I olivine) and relatively rich in Me. The wide distribution of primary Cl-rich hydrated minerals (phlogopite, amphibole and apatite) and suddenly elevation of fluid active elements at the margin of type I olivine in the sulfide ore indicates that the formation process of the Jinchuan deposit might be significantly influenced by Cl-rich fluids. The new progress in experimental petrology and dynamics simulation shows that fluid addition can effectively promote the migration of high -density sulfide slurry and it might be the main mechanism for the emplacement of the sulfide melts in the Jinchuan deposit. Combined with the spatial evolution of Cu/Ni ratios of the sulfide minerals, the Fo values of olivine and the distribution characteristics of the crystal sizes in the Jinchuan Cu-Ni sulfide deposit, it can be speculated that the magma conduit of this deposit moves from west to east.
关键词	PLATINUM-GROUP ELEMENTS SIZE DISTRIBUTION CSD STILLWATER COMPLEX COMPOSITIONAL VARIATIONS ULTRAMAFIC INTRUSION BUSHVELD COMPLEX SOUTH-AFRICA APATITE CRYSTALLIZATION ORIGIN
英文关键词	Jinchuan Cu-Ni (PGE) sulfide deposit; Two types of olivine; Cl-rich fluid; Quantitative structure analysis; Magmatic conduit metallogenic system
语种	英语
WOS研究方向	Geology
WOS类目	Geology
WOS记录号	WOS:000534690600011
来源期刊	ACTA PETROLOGICA SINICA
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/259726
推荐引用方式 GB/T 7714	Liu MeiYu,Su ShangGuo,Yao Yuan,et al. Discovery and genesis of two types of olivines and its significance to metallogeny in Jinchuan magmatic copper-nickel (PGE) sulfide deposit[J]. 中国科学院青藏高原研究所,2020,36(4).
APA	Liu MeiYu,Su ShangGuo,Yao Yuan,Wu XiaoMan,Cai Nan,&Guan QiuYun.(2020).Discovery and genesis of two types of olivines and its significance to metallogeny in Jinchuan magmatic copper-nickel (PGE) sulfide deposit.ACTA PETROLOGICA SINICA,36(4).
MLA	Liu MeiYu,et al."Discovery and genesis of two types of olivines and its significance to metallogeny in Jinchuan magmatic copper-nickel (PGE) sulfide deposit".ACTA PETROLOGICA SINICA 36.4(2020).