西天山加满特铅银矿含矿围岩地球化学特征及构造背景分析

Geochemical Characteristics and Tectonic Setting Analysis of Ore Bearing Surrounding Rocks in West Tianshan Mountain with Ga Mante Lead Silver Deposit

加满特铅银矿位于西天山伊什基里克成矿带,矿体主要赋存于下二叠统乌朗组火山岩中。通过对加满特铅银矿区含矿围岩进行岩石地球化学和LA-ICPMS锆石U-Pb测年分析,探讨火山岩形成构造环境与成岩时代。地球化学分析表明,加满特铅银矿含矿围岩为钾质玄武岩系列与钙碱性系列。微量元素和稀土元素表明,矿区火山岩产出构造环境为碰撞后板内伸展期裂谷环境。通过对含矿围岩进行锆石U-Pb测年,获得^(206)Pb/^(238)U加权平均年龄为(294.59±0.92)Ma,属早二叠世。

The Ga mante lead silver deposit is located in the Ishkirk metallogenic belt in the western Tianshan Mountains. The orebody mainly occurred in the lower Permian Wulang formation（P1w）. In this paper, the tectonic environment and diagenetic age of volcanic rocks are discussed by geochemistry and LA-ICPMS zircon U-Pb dating analysis of the ore-bearing surrounding rock in the lead and silver ore area of Ga mante. Chemical analysis shows that the surrounding rock of the lead and silver ore deposit is of the series of potash basalt and calc-alkaline. The trace elements and rare earth elements indicate that the tectonic environment of volcanic rocks in the ore area is in the rift environment of intraplate extension after collision. Zircon U-Pb dating of ore-bearing surrounding rock is carried out. The weighted average age of 206Pb/238U is（294.59 ±0.92）Ma. it belongs to the early Permian.