豆荚状铬铁矿铂族元素地球化学研究进展  

Review on Platinum-group elements geochemistry of podiform chromitites

作　　者：管涛[1,2] 黄智龙[1] 许成[1,2] 李文博[1,2] 张振亮[1,2] 严再飞[1,2] 

机构地区：[1]中国科学院地球化学研究所矿床地球化学开放研究实验室 [2]中国科学院研究生院,北京100039

出　　处：《世界地质》2004年第4期332-337,共6页World Geology

基　　金：国家重点基础研究发展规划项目(G1999043203);中国科学院知识创新工程项目(KZCX2-101)

摘　　要：豆荚状铬铁矿是蛇绿岩中特有的一类矿产,按其化学成分可分为高Cr型和高Al型两种。其中的PGE主要以RuS2和Os、Ir、Ru合金等包体形式存在,或以类质同像形式进入铬铁矿晶格。两种类型的铬铁矿均表现出负倾斜型PGE配分模式,其Pt、Pd含量相近;与高Al型铬铁矿相比,高Cr型铬铁矿有更高的Os、Ir、Ru含量,部分豆荚状铬铁矿表现出Pt、Pd相对富集的平坦到正倾斜型PGE配分模式。目前对豆荚状铬铁矿PGE含量及配分模式还缺少一个统一的解释,但其PGE地球化学可为豆荚状铬铁矿的成因及构造背景解释提供更多的信息。Podiform chromitite divided into high-Cr type and high-Al type is a kind of special mineral resouce in ophiolite. Platinum-group elements in podiform chromitites mainly occur as inclusions of laurite and Os,Ir,Ru alloy. They may enter into the lattices of chromitite in isomorphism form. Both chromitites show negatively sloping chondrite-normalized PGE pattern. Compared with high-Al chromitites,high-Cr chromitites have higher Os,Ir,Ru contents and both of them have similar Pt and Pd contents. There are also podiform chromitites showing flat to positive sloping chondrite normalized PGE pattern resulting from Pt and Pd enriched relatively. There are many discrepancy on the explanations of PGE contents and patterns of pordiform chromitites. Platinum-group elements geochemistry of podiform chromitites can provide more information on their genesis and tectonic settings.

关 键 词：铂族元素 地球化学 豆荚状铬铁矿 

分 类 号：P548.12[天文地球—构造地质学] P59[天文地球—地质学]