北京大学学报(自然科学版)

矾山碱性杂岩体中发现碳酸岩

牟保磊1, 邵济安1, 边振辉2   

  1. 1北京大学地质学系,北京,100871; 2河北矾山磷矿,河北涿鹿矾山磷矿,075641
  • 收稿日期:1997-11-28 出版日期:1999-03-20 发布日期:1999-03-20

Discovery of Carbonatite in the Fanshan Alkaline Igneous Complex in Hebei Province, China

MU Baolei1, SHAO Ji'an1, BIAN Zhenhui2   

  1. 1Department of Geology, Peking University, Beijing, 100871; 2Fanshan Phosphorus Mine, Hebei Province, China, 075641
  • Received:1997-11-28 Online:1999-03-20 Published:1999-03-20

摘要: 矾山杂岩体是中心型碱性超基性岩——碱性岩侵入体。它由三期侵入岩组成,在三期岩石形成之后有碳酸岩和正长岩脉形成。碳酸岩主要岩石类型包括:黑云母方解石碳酸岩、正长石—黑云母方解石碳酸岩、黄铁矿—方解石碳酸岩等。碳酸岩锶的含量为3364×10-6~19263×10-6, 钡的含量为323×10-6~378×10-6。碳酸岩的稀土元素∑REE为323×10-6~551×10-6, 其δEu值0.99~1.1,(La/Yb)N为291.9~759.4。碳酸岩的δ18O值是+8.6×10-3~+10.2×10-3, δ13C为-4.9×10-3。根据上述事实认为碳酸岩的物质源自岩浆。

关键词: 矾山, 碱性杂岩体, 碳酸岩

Abstract: The Fanshan complex is central type alkaline ultrabasic rock-alkaline rock intrusion. It was formed by three period intrusions and all period rocks was penetraed by carbonatites and synite vein rocks. The main type of the carbonatites rock includes: biotite calcite carbonatite, orthoclase-biotite calcite carbonatite, pyrite-calcite carbonatite and so on. Content of Strontium is 0.003364-0.019263, and content of Barium is 0.000323-0.000378 in the carbonatites. The ∑REE is 0.000323-0.000551, and the δEu value is 0.99-1.1, and the (w(La)/w(Yb))N ratio is 291.9-759.4 in the carbonatite. The δ18O value of the carbonatite is +0.0086-+0.0102, and the δ13C value of carbonatite is -0.0049. On the basic facts described above, it is thought that the carbonatite originated basically from magma.

Key words: Fanshan, alkaline igneous complex, carbonatite

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