甘肃肃北县460金矿床地质特征及原生晕地球化学找矿预测

Geological Characteristics and Primary Palo Geochemical Prospecting Prediction of the 460 Gold Deposit in Subei County,Gansu Province

460金矿床位于甘肃省酒泉市肃北县马鬃山一带,大地构造位置处于哈萨克斯坦板块星星峡—旱山微板块之黄山—红石山—路井晚古生代陆内裂谷带。区内金矿化受构造、岩浆岩、地层和变质作用的共同控制,为多期中低温热液型金矿床,热液及成矿物质主要来源于大气降水及含矿围岩,其次为岩浆,成矿时代为华力西中、晚期。金矿脉数量较多,规模较大的矿脉有110多条。选择具有代表性的10条金矿脉,通过开展野外观测、同位素地球化学、包裹体测试及原生晕岩石地球化学测量,结合室内综合研究,总结了金矿床的成矿规律,研究了各矿脉原生晕分带及构造叠加晕特征,建立了地球化学原生晕预测模型。预测结果显示,10条金矿脉深部可能赋存有21条盲矿体,经钻孔验证,见矿良好。

The 460 gold deposit is located in the Mazhongshan area of Subei County,Jiuquan City,Gansu Province,and its geotectonic position is located in the Huangshan-Hongshishan-Lujing Late Paleozoic intracontinental rift zone of the Xingxingxia-Hanshan microplate,Kazakhstan Plate.The gold mineralization in the region is jointly controlled by tectonic,magmatic rocks,stratigraphy and metamorphism.460 gold deposit is a multi-phase medium-low temperature hydrothermal deposit,the origin of hydrothermal and oreforming materials mainly come from atmospheric precipitation and ore-bearing wall rocks,mineralogenetic epoch is middle and late variscan,with a large number of gold veins and more than 110 large veins.10 representative gold veins were selected on the basis of previous data and indoor comprehensive research.The metallogenic regularity of gold deposits was summarized,and a prediction model of geochemical primary halo was established by field observation,isotopic geochemistry,inclusions test and primary halo rock geochemical survey.The predicted results show that there may be 21 blind orebodies in the depth of 10 gold veins,the drilling proved that the mine was good.