新疆琼恰特北铅锌矿地质特征及成因浅析

Geological Characters and Genesis of the Northern Qiongqiate Lead-Zinc Deposit in Xinjiang

新疆阿合奇县琼恰特北铅锌矿是近几年在西南天山地区的找矿新发现,矿床位于塔里木陆块西北缘柯坪陆缘盆地,赋矿地层为上寒武—下奥陶统丘里塔格组上段碳酸盐岩,容矿岩性为岩溶角砾岩,矿体呈似层状、不规则透镜状分布于岩溶角砾岩中,具有后生成矿特点。成矿与西南天山华力西晚期陆-陆碰撞造山事件关系密切,碰撞后造山带形成的区域流体运移进入前陆盆地,流体中的铅锌于丘里塔格组上段溶蚀崩塌形成的角砾岩中沉淀成矿。根据矿床地质地球化学特征以及与世界典型的MVT型铅锌矿床对比,笔者认为琼恰特北铅锌矿床属于MVT型铅锌矿矿床。

The northern Qiongqiate Lead Zinc deposit in the Ajugqi County of Xinjiang is a new prospecting discovery within the southwest Tianshan area in recent years. This deposit is located in the Keping marginal basin on the northwestern margin of the Tarim Basin, the ore bearing strata are Triassic carbonate rocks in the Upper Cambrian Lower Ordovician Qiulitage Forma tion, the host block is karst breccias, while the ore body shows stratiform and irregular lens dis tribution in karst breccia, with the characteristics of subsequent ore deposit. The mineralization is closely related to the late Hercynian continental continental collision orogeny in the southwest Tianshan. During the collision, the fluid was formed in the orogenic belt and migrated into the foreland basin, the rich ore bearing fluid of was precipitated in karst breccias from the upper part of the Qiulitage Formation to from the lead and zinc mineralization. According to the geological geochemical characteristics of this deposit and the comparison with typical MVT type lead zinc deposits in the world, it is believed that the northern Qiongqiate lead zinc deposit belongs to the MVT type lead zinc deposit.