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现代地质 ›› 2008, Vol. 22 ›› Issue (2): 181-189.

• 岩石学与矿床学 • 上一篇    下一篇

康定—泸定地区变质侵入岩的地质地球化学特征及其构造环境

李志红1,罗照华2,陈岳龙2,赵俊香3   

  1. 1中国地质科学院 地质研究所 国土资源部同位素地质重点实验室,北京100037; 2中国地质大学 地球科学与资源学院,北京100083;3中国地震局 地壳应力研究所,北京100085
  • 收稿日期:2007-10-17 修回日期:2008-03-09 出版日期:2008-02-20 发布日期:2008-02-20
  • 作者简介:李志红,女,助理研究员,1975年出生,同位素地球化学专业,主要从事同位素地球化学的研究工作。 Email: lizh1129@cags.net.cn
  • 基金资助:

    国家自然科学基金项目(40173007,40234052)

Geology and Geochemistry of the Kangding-Luding Metamorphosed Intrusions and Implication for Tectonic Setting

LI Zhi-hong1,LUO Zhao-hua2,CHEN Yue-long2,ZHAO Jun-xiang3   

  1. 1Laboratory of Isotope Geology of the Ministry of  Land and Resources,Institute of Geology, Chinese Academy of Geological Sciences,
    Beijing100037, China;
    2School of Earth Sciences and Resources,China University of Geosciences, Beijing100083, China;
    3China Institute of Crustal Dynamics, China Earthquake Administration, Beijing100085, China
  • Received:2007-10-17 Revised:2008-03-09 Online:2008-02-20 Published:2008-02-20

摘要:

康定—泸定地区出露的新元古代变质侵入岩位于扬子板块西缘北段。通过详细的野外地质特征、岩相学、矿物学及岩石地球化学等方面的研究,确定岩石组合为辉长岩、石英闪长岩、英云闪长岩、花岗闪长岩、二长花岗岩和正长花岗岩,其中以中酸性岩为主,具有钙碱性演化特征;长石成分主要为钠长石—更长石—中长石,含水矿物角闪石、黑云母广泛存在;主量元素显示钙碱性分异趋势;微量元素呈现典型的岛弧环境地球化学特征;稀土配分模式呈右倾型;在构造环境判别图中,该变质侵入岩样品均投影于火山弧区域。综合以上特征表明康定—泸定地区变质侵入岩在新元古代处于与俯冲有关的岩浆弧环境。

关键词: 康定—泸定, 变质侵入岩, 地质地球化学特征, 岩浆弧

Abstract:

The Kangding-Luding metamorphosed intrusions are distributed in northwestern margin of the Yangtze block. On the basis of the field geological characteristics, petrography, mineralogy and geochemistry, we demonstrate that rock types include gabbro, quartzdiorite, tonalite, granodiorite, adamellite, syenogranite, in which intermediate acid rocks are majority; The rocks are dominantly moderate-K calc-alkaline series; Components of plagioclase include albite, oligoclase and andesine, hornblende and biotite exist extensively; The intrusions have calc-alkaline differential trend in major element compositions. Their trace elements show typical geochemical characteristics of island arc setting; REE patterns are of slightly rightinclined type; On the diagram of tectonic settings, they are mainly located at the range of VAG. Above mentioned characteristics suggest that the Kangding-Luding metamorphosed intrusions were formed at the magmatic arc setting.

Key words: Kangding-Luding, metamorphosed intrusion, geological and geochemical characteristics, magmatic arc

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