南秦岭古生代盆地演化中幕式流体过程及成岩成矿效应

从南秦岭古生代盆地构造-沉积演化出发,通过分析古生界不同层位流体成岩成矿事实与盆地发展演化之间的关系,探讨了南秦岭早古生代—泥盆纪演化时期多幕流体过程和成岩成矿效应。幕式流体成岩成矿最早可追溯到早寒武世,区域上从东到西形成了重要的碳硅质岩中重晶石/毒重石矿床及金、铂族元素矿化;早、中志留世继续发展,形成了钠长石岩、重晶石岩、铁碳酸盐岩、硅质岩与铅-锌、金矿床;中泥盆世为最强烈的一次热水沉积活动,其规模大、热水沉积产物多样,形成了泥盆系硅质岩-钠长石岩-重晶石岩-铁白云石岩中的铅锌(铜)矿床、铁白云石硅质岩中铅锌(铜)矿床以及钠长石角砾-铁白云石板岩中金-铜矿床。

Episodic-Fluid Process and Effect of Diagenesis and Mineralization in Evolution of Paleozoic Basins in South Qinling

Following the process of tectonic and sedimentary evolution fo South Qniling basin,by analyzing the relationship between the phenomena of digeneisis and mineralization in different strata in the basin and the development and evolution,this paper discusses the episodic-fluid process and the diagenesis and mineralization from the early Paleozoic to Devonian,and establishes the sequences of diagenesis and mineralization.The earliest episodic-fluid activity in Paleozoic basin of South Qinling happened in early Cambrian when the barite/witherite deposits and mineralization of Au-PGE with carbonaceous-siliceous rock were formed from the east to the west.During ealy-middle Silurian,episodic-fluid activity produced albite rock,barite rock,ferruginous carbonate rock,siliceous rock and ore deposits of Pb-Zn and mineralization of Au.During the Devonian,the strongest hydrothermal sedimentatione took place in siliceous rock,and albite rock,barite rock,ankerite slate and Pb-Zn(Cu)ore deposits,ankerite siliceous rock type Pb-Zn(Cu)ore deposits,and Au,Cu deposits in albite rock/ankerite slate were formed.