大吉山花岗岩体黑云母地球化学特征及其成岩成矿意义  

COMPOSITIONAL CHARACTERISTICS AND PETROLOGICAL SIGNIFICANCE OF THE BIOTITE IN THE DAJISHAN GRANITE,JIANGXI PROVINCE

作　　者：蒋国豪[1] 胡瑞忠[1] 谢桂青[1] 赵军红[1] 

机构地区：[1]中国科学院地球化学研究所矿床重点实验室

出　　处：《矿物岩石》2005年第1期58-61,共4页Mineralogy and Petrology

基　　金：国家杰出青年基金(49925309)

摘　　要：　通过对大吉山花岗岩中黑云母化学成分特征的研究,发现大吉山黑云母花岗岩体中黑云母属铁镁黑云母,而二云母花岗岩中黑云母属富铁黑云母。黑云母花岗岩是壳幔混合的产物,而 阶段二云母花岗岩属壳源花岗岩。大吉山黑云母花岗岩成岩过程中可能存在玄武岩岩浆的底侵作用,这种底侵作用可能是大吉山钨矿成岩成矿的地球动力学背景之一。大吉山花岗岩体在演化过程中存在流体分异作用,与二云母花岗岩共存的流体更富氟,可能这种富氟和钨等成矿元素的热液流体形成了著名的大吉山钨矿。The compositional characters of the biotites of the Dajishan granites were discussed in this paper. The biotite in the biotite granite is Fe-Mg biotite and the biotite of the two-mica granite is Fe-rich biotite. The biotite granite was originated from the blend of the crust and the mantle substance and the two-mica granite was crust granite. During the formation of biotite granite,there exited the underplating of the basalt magma and the hydrothermal fluid exsolution.The underplating of the basalt magma may be a favourable dynamic background for the formation of the granite and the tungsten deposit. Based on the data of the composition of the biotites from the Dajishan granite, the hydrothermal fluid in the two-mica granite was enrich in fluorine. Maybe this hydrothermal fluid rich in fluorine and tungsten formed the famous Dajishan tungsten deposit.

关 键 词：花岗岩体 黑云母 成矿 地球化学特征 底侵作用 地球动力学背景 分异作用 成岩 流体 共存 

分 类 号：P588[天文地球—岩石学] P618[天文地球—地质学]