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DOI	10.1007/s00126-017-0739-3
	Oxidation state inherited from the magma source and implications for mineralization: Late Jurassic to Early Cretaceous granitoids, Central Lhasa subterrane, Tibet
	Cao, MingJian; Qin, KeZhang; Li, GuangMing; Evans, Noreen J.; McInnes, Brent I. A.; Li, JinXiang; Zhao, JunXing
通讯作者	Cao, MJ (通讯作者)
发表日期	2018
ISSN	0026-4598
EISSN	1432-1866
起始页码	299
结束页码	309
卷号	53 期号:3
英文摘要	Arc magmas are more oxidized than mid-ocean ridge basalts; however, there is continuing debate as to whether this higher oxidation state is inherited from the source magma or developed during late-stage magmatic differentiation processes. Well-constrained Late Jurassic to Early Cretaceous arc-related intermediate to felsic rocks derived from distinct magma sources provide us with a good opportunity to resolve this enigma. A series of granitoids from the western Central Lhasa subterrane were analyzed for whole-rock magnetic susceptibility, Fe2O3/FeO ratios, and trace elements in zircon. Compared to Late Jurassic samples (1.8 +/- 2.0 x 10(-4) emu g(-1) oe(-1), Fe3+/Fe-total = 0.32 +/- 0.07, zircon Ce4+/Ce3+* = 15.0 +/- 13.4), Early Cretaceous rocks show higher whole-rock magnetic susceptibility (5.8 +/- 2.5 x 10(-4) emu g(-1) oe(-1)), Fe3+/Fe-total ratios (0.43 +/- 0.04), and zircon Ce4+/Ce3+* values (23.9 +/- 22.3). In addition, positive correlations among whole-rock magnetic susceptibility, Fe3+/Fe-total ratios, and zircon Ce4+/Ce3+* reveal a slight increase in oxidation state from fO(2) = QFM to NNO in the Late Jurassic to fO(2) = similar to NNO in the Early Cretaceous. Obvious linear correlation between oxidation indices (whole-rock magnetic susceptibility, zircon Ce4+/Ce3+*) and source signatures (zircon epsilon Hf(t), T-DM (C) ages) indicates that the oxidation state was predominantly inherited from the source with only a minor contribution from magmatic differentiation. Thus, the sources for both the Late Jurassic and Early Cretaceous rocks were probably influenced by mantle wedge-derived magma, contributing to the increased fO(2). Compared to ore-forming rocks at giant porphyry Cu deposits, the relatively low oxidation state (QFM to NNO) and negative epsilon Hf(t) (-16 to 0) of the studied granitoids implies relative infertility. However, this study demonstrates two potential fast and effective indices (fO(2) and epsilon Hf(t)) to evaluate the fertility of granitoids for porphyry-style mineralization. In an exploration context for the west Central Lhasa subterrane, features indicative of potential fertility might include more oxidized, positive epsilon Hf(t), young rocks (< 130 Ma).
关键词	ZIRCON U-PB PORPHYRY CU-MO HF ISOTOPE REDOX STATE TECTONIC EVOLUTION METALLOGENIC BELT TRACE-ELEMENT GANGDESE BELT ORE-DEPOSITS ARC MAGMAS
英文关键词	Oxidation state; Magnetic susceptibility; Fe3+/Fe-total ratios; Zircon Ce4+/Ce3+*; Central Lhasa subterrane
语种	英语
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
WOS类目	Geochemistry & Geophysics ; Mineralogy
WOS记录号	WOS:000425106700001
来源期刊	MINERALIUM DEPOSITA
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/259191
推荐引用方式 GB/T 7714	Cao, MingJian,Qin, KeZhang,Li, GuangMing,et al. Oxidation state inherited from the magma source and implications for mineralization: Late Jurassic to Early Cretaceous granitoids, Central Lhasa subterrane, Tibet[J]. 中国科学院青藏高原研究所,2018,53(3).
APA	Cao, MingJian.,Qin, KeZhang.,Li, GuangMing.,Evans, Noreen J..,McInnes, Brent I. A..,...&Zhao, JunXing.(2018).Oxidation state inherited from the magma source and implications for mineralization: Late Jurassic to Early Cretaceous granitoids, Central Lhasa subterrane, Tibet.MINERALIUM DEPOSITA,53(3).
MLA	Cao, MingJian,et al."Oxidation state inherited from the magma source and implications for mineralization: Late Jurassic to Early Cretaceous granitoids, Central Lhasa subterrane, Tibet".MINERALIUM DEPOSITA 53.3(2018).