西山湾羊场银矿床异常特征及找矿标志

Characteristics of Geochemical Anomaly of Xishanwanyangchang Silver Deposit and Clue for Prospecting

西山湾羊场银矿床位于华北地台北缘狼山—渣尔泰山中—新元古代裂谷带东段,赋存于白垩系下统白女羊盘组(K_1bn)酸性火山岩中,赋矿围岩主要为流纹岩、流纹斑岩、流纹质角砾岩。矿区断裂构造发育,矿床受断裂构造控制明显,含矿流纹斑岩破碎明显,具较强的硅化、黄铁矿化、萤石化等特征。该矿床的水系沉积物异常元素组合主要为Ag,W,As,Au,Sb,Pb,Bi,Mo,Zn,Cu,Hg,具有明显的浓度分带和组分分带,Ag异常极值点有一定的连续性。岩石地化异常Ag,Au,As,Sb,W,Mo等多元素组合异常套和较好。

Xishanwanyangehang silver deposit is located in the east section of Langshan-Zha' ertaishan Mesoproterozoic rift zone of the northern margin of the north china plate,and it is hosted in the volcanic rock of lower series of Cretaceous Bainvyangpan Formation(K_1bn).Its host rock mainly is rhyolite,rhyolite porphyre and rhyolite breccia.Faulted structure is well-developed in the mine area,and the deposit is clearly controlled by fractures.Ore-bearing rhyolite porphyre is broken significantly,and it is characteristics of silication,pyritization and fluoritization.The anomaly element combination is Ag,W,As,Au,Sb,Pb,Bi,Mo,Zn,Cu,Hg for stream sediment survey,and they has the distinct zonation in concemtration and component,and maximum of silver anomaly is continuous.The lithogeochemical anomalies of Ag,Au,As,Sb,W,Mo fit better.