Association of Neoproterozoic A- and I-type granites in South China: Implications for generation of A-type granites in a subduction-related environment
文献类型：期刊论文
| 作者 | Zhao, Xin-Fu1; Zhou, Mei-Fu1; Li, Jian-Wei2; Wu, Fu-Yuan3 |
| 刊名 | CHEMICAL GEOLOGY
 |
| 出版日期 | 2008-11-30 |
| 卷号 | 257期号:1-2页码:1-15 |
| 关键词 | A-type granite I-type granite Charnockite Yangtze Block Neoproterozoic |
| ISSN号 | 0009-2541 |
| DOI | 10.1016/j.chemgeo.2008.07.018 |
| 文献子类 | Article |
| 英文摘要 | Neoproterozoic magmatism in the Yangtze Block of South China produced voluminous S- and I-type granites, and sparse A-type granites. The Daxiangling A-type granitic pluton is spatially associated with the Shimian I-type pluton at the western margin of the Yangtze Block. Both plutons have similar SHRIMP zircon U-Pb ages of similar to 800 Ma and are slightly younger than the tonalite-trondhjemite-granodiorite (TTG) gneisses in the area. The Shimian pluton is composed of granite and monzogranite with high SiO(2) (69.3-76.6 wt.%), Na(2)O (2.79-3.80 wt.%) and K(2)O (3.94-5.87 wt.%), and low Fe(2)O(3) (0.96-3.06 wt.%) and MgO (0.12-0.50 wt.%). The Daxiangling pluton consists of alkali-feldspar granites with higher SiO(2) (76.3-79.3 wt.%) and lower Al(2)O(3) (10.6-11.9 wt.%) and CaO (0.21-0.55 wt.%) than the Shimian granites. Both plutons are slightly peraluminous (A/CNK=1.00-1.12) and belong to the high-K, calc-alkaline series. The Daxiangling alkali-feldspar granites have much higher Zr, Hf, Ga and HREE, and lower Sr than the Shimian granites. On the chondrite-normalized REE diagram, both plutons are enriched in LREE, but the rocks of the Daxiangling pluton show relatively flat patterns because of their higher HREE contents. Their primitive-mantle normalized spidergrams display negative Eu, Nb, Ta, Sr, P and Ti anomalies. Both plutons have nearly identical whole-rock Nd and zircon Hf isotopic compositions (epsilon(Nd)(t)=+1 and epsilon(Hf)(t)=+5 to +9), similar to the TTG gneisses. We suggest that the I-type granites of the Shimian pluton were produced by dehydration melting of the TTG rocks as a result of underplating of mantle-derived mafic magmas. The rocks above the I-type magma source may have been converted to charnockites by heating and dehydration. With increasing temperatures, the charnockites underwent partial melting at temperatures >900 degrees C to produce A-type magmas. Both the A- and I-type granites formed at an extensional active continental margin, perhaps in a back-arc environment. A-type granites with mantle-like isotopic signatures may be reworked or recycled front juvenile crustal rocks. The association of A- and I-type granites suggests that aluminous A-type granite is most probably derived from a charnockite source heated by large-scale magmatic underplating, rather than a tonalite source. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved. |
| WOS关键词 | PB ZIRCON GEOCHRONOLOGY ; NEODYMIUM ISOTOPE EVIDENCE ; YANGTZE BLOCK ; LU-HF ; TECTONIC EVOLUTION ; NORTHERN MARGIN ; SOUTHEASTERN AUSTRALIA ; CRUSTAL EVOLUTION ; MAFIC INTRUSIONS ; SICHUAN PROVINCE |
| WOS研究方向 | Geochemistry & Geophysics |
| 语种 | 英语 |
| WOS记录号 | WOS:000261564200001 |
| 出版者 | ELSEVIER SCIENCE BV |
| 资助机构 | CRCG University of Hong Kong ; CRCG University of Hong Kong ; CRCG University of Hong Kong ; CRCG University of Hong Kong ; CRCG University of Hong Kong ; CRCG University of Hong Kong ; CRCG University of Hong Kong ; CRCG University of Hong Kong |
| 源URL | [http://ir.iggcas.ac.cn/handle/132A11/70016]  |
| 专题 | 中国科学院地质与地球物理研究所 |
| 通讯作者 | Zhao, Xin-Fu |
| 作者单位 | 1.Univ Hong Kong, Dept Earth Sci, Hong Kong, Hong Kong, Peoples R China 2.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Wuhan 430074, Peoples R China 3.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China |
| 推荐引用方式 GB/T 7714 | Zhao, Xin-Fu,Zhou, Mei-Fu,Li, Jian-Wei,et al. Association of Neoproterozoic A- and I-type granites in South China: Implications for generation of A-type granites in a subduction-related environment[J]. CHEMICAL GEOLOGY,2008,257(1-2):1-15. |
| APA | Zhao, Xin-Fu,Zhou, Mei-Fu,Li, Jian-Wei,&Wu, Fu-Yuan.(2008).Association of Neoproterozoic A- and I-type granites in South China: Implications for generation of A-type granites in a subduction-related environment.CHEMICAL GEOLOGY,257(1-2),1-15. |
| MLA | Zhao, Xin-Fu,et al."Association of Neoproterozoic A- and I-type granites in South China: Implications for generation of A-type granites in a subduction-related environment".CHEMICAL GEOLOGY 257.1-2(2008):1-15. |
入库方式： OAI收割
来源：地质与地球物理研究所
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