安徽省东至—宁国地区燕山期侵入岩地球化学特征及找矿意义

Geochemical characteristics and prospecting significance of Yanshanian intrusive rocks in East-Ningguo area, Anhui Province

通过对皖南东至-宁国一带燕山期侵入岩的岩石学、微量元素地球化学、侵位时代的分析,探讨了其岩浆来源及演化规律。结果表明:研究区燕山期侵入岩轻、重稀土分馏程度高,铕负异常不明显,岩浆为地壳熔融作用的产物,部分岩体分离结晶作用明显。区内找矿方向宜以中、小型矽卡岩型、钨-钼矿床为主,金矿与前寒武纪地层的相对高背景有关。

Based on the analysis of petrology,trace element geochemistry and emplacement age of Yanshanian intrusive rocks from east to Ningguo in southern Anhui,the magma source and evolution law are discussed.The results show that the Yanshanian intrusive rocks in the study area have high fractionation of light and heavy rare earth elements,and the negative Eu anomaly is not obvious.The magma is the product of crustal melting,and the fractional crystallization of some rock masses is obvious.The main prospecting directions in this area are medium and small skarn and W-Mo deposits.The gold deposits are related to the relative background of Precambrian strata.