云南巴打湾沉积型重晶石矿床控矿条件研究

A STUDY ON THE ORE-CONTROLLING CONDITION OF THE BADAWAN SEDIMENTARY BARITE DEPOSIT IN YUNNAN

云南宁蒗巴打湾矿区重晶石矿产于上奥陶统。矿体呈层状、似层状和透镜状产出 ,矿石化学组分与围岩岩性组合关系密切 ,且其Co/Ni均小于或等于 1。矿区矿石组构特征与含矿赋矿围岩的沉积构造特征具有密切的对应性。巴打湾重晶石矿床位于扬子准地台西缘构造过渡带 ,重晶石矿形成时矿区处于半封闭盆地浅海相 滨海相 ,且海水由深向浅演化 。

The barite deposit of Badawan mining district in Yunnan is hosted in the upper Ordovician rock beds. And the barite orebody is stratified, stratification-like or lenticular. The chemical composition of Badawan barite ore has a close relation with the lithological association of its surrounding rocks, and the Co/Ni is less than 1 or equals to 1. The characteristics of the ore texture in the mining district have a good correspondence with the sedimentary structure of its country rock. The Badawan barite deposit lies on the western border of the Yangtze Platform which is a structural transition belt. While the barite deposit was forming, the mining district was located in a semi-enclosed basin from shallow sea to littoral facies, and the water depth decreased progressively whereas the oxidation degree increased gradually.