内蒙古西山湾羊场火山岩型银多金属矿床地化异常特征及控矿因素

Characteristics of Geochemical Anomalies and Ore-Controlling Factors of the Xishanwanyangchang Volcanic-Hosted Silver Polymetallic Deposit,Inner Mongolia

通过1∶5万水系沉积物测量,获得Ag、W、As、Au、Sb、Pb、Bi、Mo、Zn、Cu、Hg等多元素组合异常,这些异常具有明显的浓度分带和组分分带。运用岩石地球化学测量方法进行异常查证,进一步获得Ag、Au、As、Sb、W、Mo等多元素套合较好的岩石地球化学异常。通过地表槽探工程揭露,圈定出具一定规模的矿化体。深部钻探工程验证确定银多金属矿体的存在。矿体主要产于硅化较强的流纹岩、流纹斑岩、流纹质角砾岩中,以及火山岩与花岗岩的接触带部位,矿床受断裂构造控制明显,赋矿围岩为下白垩统白女羊盘组(K1bn)酸性火山岩。

The element combination anomalies of Ag, W, As, Au, Sb, Pb, Bi, Mo, Zn, Cu and Hg, which show distinct zonation distributions in both concentrations and components, was obtained by streams sediments survey. The lithogeochemical survey indicated that lithogeochemical anomalies of Ag, Au, As, Sb, W and Mo are fit well. Orebodies and mineralization belts of Ag have been delineated by trench exploration. Drilling engineering identified that silver polymetallic orebodies are hosted in Rhyolite, rhyolite porphyry, and rhyolite breccia of lower series of the Cretaceous Bainvyangpan Formation （K_1 bn） as well as the contact zone of the volcanic rock and granite. The ore deposit is controlled significantly by faults.