桂东北地区几个加里东期花岗岩体的地球化学特征及其构造环境判别

Judging for characterstics of geochemical and structural environment of several caledonian granitoids in northeast Guangxi

通过对该区花岗岩的常量元素、稀土元素及微量元素成分分析对比,利用岩石化学特征并结合岩体产出地质条件,对花岗岩形成的构造环境进行了综合判别。提出桂东北花岗岩具有相同的成因和来源,属同一岩浆结晶分异演化而来。结晶分异作用为花岗岩的主要成岩方式。越城岭、苗儿山和海洋山岩体主要形成于同碰撞的挤压构造环境下,而大宁岩体总体构造环境为处于碰撞前向同碰撞转换的挤压构造环境。

By comparison and compositional analysis of major, rare earth and trace elements of the granitoids in the region, a comprehensive discriminant analysis on the structural environment for granite forming was made , by use of rock geochemistry and combined with the granite forming geological condition. It is proposed that the granitoids in northeast Guangxi possess same genesis and source, which came from the same magmatic crystallization differentiation in Northeast Guangxi. Crystallization differentiation for granite is the main diagenesis mode. Yue Chengling , Miao Ershan and Hai Yangshan granitic rocks were mainly formed in syngenetic collision environment, whereas Da Ning granitic rock is from pre-plate collision to collision environment.