西准谢米斯台乌什加嘎衣提一带金矿地质特征研究

Study on Geological Characteristics of Au Deposits of Wushijiagayiti on Xiemisitai Mountain,West Junggar

西准谢米斯台乌什加嘎衣提一带金成矿潜力突出,以典型金矿床及矿点为研究对象,研究含矿石英脉微量元素及流体包裹体氢氧同位素地球化学特征,简析重要成矿条件、成矿物质来源。乌什加嘎衣提一带矿(化)脉靠近花岗岩体分布,乌什加噶衣提金矿床(1)、(2)号带,布来萨拉金铜矿床(1)、(2)号带及乌金I矿点(1)号带靠近岩体,产于NEE向构造薄弱部位;乌金I矿点(2)、(3)号带,乌金II矿点(1)、(2)号带远离岩体,产于NWW向构造薄弱部位;矿(化)脉以石英脉型为主。含金石英脉低REE总量、具富LREE的右倾分布型式。富集Cs,Rb,Th,Ba相对亏损,Hf,Zr,Sm,Tb,Y,Yb,Lu等较低;δ^(18)O_(V-SMOW)、δD_(V-SMOW)分布范围窄,前者多小于10‰。认为区内靠近岩体的NEE向、远离岩体的NWW向断裂构造及构造薄弱部位为重要控矿构造,成矿物质来源于后碰撞环境挤压-伸展转换期的上下地壳混熔阶段。

Studing the geological characteristics and geochemical characteristics of related quartz vein of Au deposits of the region of Wushijiagayiti,this paper aims to discuss its important ore-controlling conditions and ore-forming material source.The Au ore bodies can be divided into two types by forms,which ones distributed in the NEE breaks closing to intrusive bodies and intersecting the NE faults which across by the bodies,the other ones distributed in NWW breaks keeping away from the bodies and intersecting the NE faults.The ore bodies belong to the type of quartz vein and altered rock partly. The related quartz vein is charactered by rich LREE and right deviation type of REE Curve,rich Cs, Rb, Th, low Ba, Hf, Zr, Sm, Tb, Y, Yb, Lu, and Narrow range of distribution of δ18OV-SMOW（mainly less than 10‰）, δDV-SMOW. The study suggests the NEE, NWW breaks above are main ore-controlling breaks, and the ore-forming bachground is extrusion-extension transition period of post-collision phase, and the ore-forming material can be trace to the mixing melt of upper and lower crust.