| 川西康定—丹巴地区新元古代基性岩墙成因及源区性质 |
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| 引用本文： | 林广春,董俊超.川西康定—丹巴地区新元古代基性岩墙成因及源区性质[J].中国地质,2013,40(6):1793-1805. |
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| 作者姓名： | 林广春 董俊超 |
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| 作者单位： | 1. 长安大学地球科学与资源学院，陕西 西安 710054；2. 西部矿产资源与地质工程教育部重点实验室，陕西 西安 710054；3. 陕西中核资源有限公司，陕西 西安 710054 |
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| 基金项目： | 中央高校基本科研业务费专项基金(CHD2010JC038)资助。 |
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| 摘 要： | 提要：扬子地块西缘新元古代岩浆岩分布广泛，目前对其成因和构造背景的认识还存在很大争议。本文报道了川西康滇裂谷北段康定—丹巴地区新元古代基性岩墙的岩石学、元素地球化学和Sm-Nd同位素特征，探讨其岩石成因、岩浆源区性质和岩浆熔融深度。结果表明岩石样品属拉斑系列，形成于板内裂谷环境，岩浆在上升侵位过程中受到了初生岛弧地壳物质不同程度的混染。岩浆起源于亏损地幔源区，是尖晶石地幔橄榄岩部分熔融的产物，很可能与导致Rodinia超级大陆裂解的新元古代地幔柱事件有关。
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| 关 键 词： | 基性岩墙 康滇裂谷 新元古代 Rodinia超级大陆 |
Petrogenesis and source characteristics of Neoproterozoic mafic dykes in Kangding-Danba area, western Sichuan |
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| LIN Guang-chun,DONG Jun-chao.Petrogenesis and source characteristics of Neoproterozoic mafic dykes in Kangding-Danba area, western Sichuan[J].Chinese Geology,2013,40(6):1793-1805. |
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| Authors: | LIN Guang-chun DONG Jun-chao |
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| Abstract: | Abstract: Neoproterozoic magmatic rocks are widespread on the western margin of the Yangtze block, and their genesis and tectonic setting have long been problems of hot debate. Petrological, geochemical and Sm-Nd isotopic data are reported for Neoproterozoic Kangding-Danba mafic dykes in the Kangdian rift on the western margin of the Yangtze block. This paper deals with petrogenesis and magma source characteristics of these rocks. The rock samples are of tholeiite series, and their geochemical and Nd isotopic characteristics suggest that they were generated in an intraplate setting with variable degrees of contamination of young island arc crust during magma ascending. The magma was generated by partial melting of DM mantle source region within the spinel stability field, and was probably related to Neoproterozoic plume event related to the breakup of Rodinia supercontinent. |
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| Keywords: | mafic dykes Kangdian rift Neoproterozoic Rodinia supercontinent |
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