赣南余田群双峰式火山岩地球化学特征与成因  

Geochemical Characteristics and Genesis of Bimodal Volcanic Rocks of Yutian Group in Southern Jiangxi

作　　者：刘帅[1] 黄美化[1] 巫建华[1] 管太阳[1] 

机构地区：[1]东华理工学院,江西抚州市344000

出　　处：《矿业研究与开发》2007年第1期1-4,共4页Mining Research and Development

基　　金：核工业总公司重点攻关项目(Y1218960401)

摘　　要：余田群菖蒲组火山岩属典型的双峰式火山岩,(中)基性火山岩稀土总含量小,REE变化范围大,且低于地壳的REE值;酸性火岩稀土总含量大,高于地壳的REE值。从基性火山岩到酸性火山岩,随着SiO2的增加,轻重稀土分馏程度越来越高。通过对火山岩岩浆性质的研究可知,(中)基性火山岩明显具富集地幔性质,且经受过地壳物质或花岗质岩石的混染;酸性火山岩岩浆则具有壳源性质。Volcanics of Changpu formation of Yutian group is typical bimodal volcanic rock. There is less Y. REE in the （intermediate） basic volcanic rock, being lower than the ∑ REE value of earth crust, and the change range of ∑ REE is large. The total content of REE in the acid volcanic rock is high, being higher than the ∑ REE value of earth crust. With the increase of SiO2, from the basic volcanic rock to the acid volcanic rock, the fractional degree of HREE and LREE becomes more and more high. The research of the volcanic magma feature has shown that the （intermediate） basic volcanic rock obviously indicates the characteristics of enriched mantle, and is mixed with the crust substance or granitic rocks; the magma of acid volcanic rock mainly has the characteristics of crust source.

关 键 词：双峰式火山岩 分异程度 混染 赣南 稀土 

分 类 号：P618.51[天文地球—矿床学]