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DOI	10.1130/B35370.1
	Permo-Triassic granitoids, Hainan Island, link to Paleotethyan not Paleopacific tectonics
	He H.; Wang Y.; Cawood P.A.; Qian X.; Zhang Y.; Zhao G.
发表日期	2020
ISSN	167606
起始页码	2067
结束页码	2083
卷号	132 期号:2021-09-10
英文摘要	Hainan Island may have lain at the boundary between the Tethyan and Pacific domains since the late Paleozoic. Permo-Triassic granitoids outcropped on the island provide insight into Mesozoic tectonic evolution and potential dynamics. Based on analyses of zircon U-Pb geochronological and Hf-O isotopic data, along with whole-rock elemental and Sr-Nd isotopic data, the Permo-Triassic granitoids are divided into three groups: Late Permian (256-252 Ma) gneissic granitoids (Group 1), Early-Middle Triassic (247-244 Ma) massive granitoids (Group 2), and Middle-Late Triassic (242-225 Ma) massive granitoids (Group 3). Groups 1 and 2 exhibit similar elemental and Sr-Nd isotopic compositions with εNd(t) values ranging from -6.71 to -3.25. Group 1 is characterized by gneissic foliation and calc-alkaline I-type geochemical affinities with negative Nb-Ta and Ti anomalies; it has low εHf(t) (-4.2~+0.2) and high γ18O values (9.35-10.46‰), possibly related to derivation of a metabasite source in a continental arc setting. The Group 2 samples are peraluminous massive granitoids with slightly high A/CNK ratios of 1.00-1.31, d18O values (8.85-11.75‰), and high Sr/Y ratios but low εHf(t) (-8.7~+1.6) values. They may have originated from the mixed source of greywacke and metabasite, indicating a compressive tectonic setting. The Group 3 high-K calc-alkaline granitoids have high zircon temperatures (842-867 °C) and show the geochemical signatures of A-type granites. They are featured by slightly low whole- rock εNd(t) and zircon εHf(t) values, suggestive of the derivation from a metabasite-greywacke source in an extensional setting. In combination with other geochronological and geochemical data from Hainan Island, it is proposed that the Permian-Triassic igneous magmatism in Hainan Island reflects a continuous amalgamation process from back-arc consumption (272-252 Ma) to orogenic assembly (251-243 Ma) and orogenic collapse (242-225 Ma) between the South China and Indochina Blocks. Such a temporal- spatial pattern for the Hainan granitoids is consistent with that along the Truong Son, Jinshajiang-Ailaoshan-Song Ma tectonic zone, suggesting dominant control of Paleotethyan domain instead of Paleopacific tectonics. © 2019 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184730
作者单位	Guangdong Provincial Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Guangzhou, 510275, China; Southern Laboratory of Ocean Science and Engineering, Zhuhai, 519082, China; School of Earth, Atmosphere and Environment, Monash University, Melbourne, VIC 3800, Australia
推荐引用方式 GB/T 7714	He H.,Wang Y.,Cawood P.A.,et al. Permo-Triassic granitoids, Hainan Island, link to Paleotethyan not Paleopacific tectonics[J],2020,132(2021-09-10).
APA	He H.,Wang Y.,Cawood P.A.,Qian X.,Zhang Y.,&Zhao G..(2020).Permo-Triassic granitoids, Hainan Island, link to Paleotethyan not Paleopacific tectonics.Bulletin of the Geological Society of America,132(2021-09-10).
MLA	He H.,et al."Permo-Triassic granitoids, Hainan Island, link to Paleotethyan not Paleopacific tectonics".Bulletin of the Geological Society of America 132.2021-09-10(2020).