化探在明山金矿的找矿效果

RESULTS OF GEOCHEMICAL PROSPECTING IN MINGSHAN GOLD DEPOSIT，GUANGXI

桂西北微细粒型金矿床（点）多是由化探发现，明山金矿即是在１：２０万和１：５万区域化探所圈定的异常中，经三级检查、二级查证，并配合深部揭露发现的大型金矿床。矿床位于不同构造单元衔接地带的断裂构造部位，赋矿层位为中三叠统百逢组，主要富集于黄铁矿、毒砂中，与矿化关系密切的围岩蚀变有硅化、黄（褐）铁矿化、毒砂化、绢云母及碳酸盐岩化，化探标志明显，显示了化探找金的效果及意义。

Most of microfine－grained type gold deposits（occurences）in northwestern Guangxiare found by geochemical prospecting，For example， Mingshangold deposit，a lareg-scalegold deposit，is found by class 3 investigation and class 2 verification in the anomaly of 1：200 000 scale and 1：50000 scale regional geochemical prospecting. The Mingshan golddeposit is situated in the fractures of the connexion of different tectonic units. Gold bodieslie in the Baifeng Formation of Middle Triassic Series. The gold occurs majorly in pyriteand arsenopyrite. The alternations reiated to the gold mineralization are silicification，pyritization（limonitization），arsenopyritization，sericitization and carbonatization. Obviousgeochemical prospecting marks show the results and significances of geochemicalprospecting for gold deposits.