浙江八面山特大型萤石矿床的沉积成矿特征

Sedimentary Genesis Feature of Bamianshan Unusual Large Fluorite Deposit in Zhejiang Province

八面山萤石矿床是近年来发现的特大型萤石矿床,通过成矿地质背景,矿体与矿石特征,容矿岩系岩石化学组成特征,岩石与矿石稀土元素特征,钐—钕同位素特征等研究,探讨了矿床的沉积成矿特点。结果充分说明,八面山萤石矿床是一个以沉积为主,后经热液改造的特大型萤石矿床。依据上述分析数据,同时结合容矿围岩和矿体的地质特征,可以推测,八面山萤石矿床是寒武系沉积岩作为矿源层,为萤石矿床的形成提供了必要的物源。后期岩浆作用只是对部分矿体进行了不同程度的改造,局部形成了构造带中的陡倾斜脉状矿体。

Bamianshan is an unusual large fluorite deposit discovered in recent years.This paper studies the geologic background of mineralization,geological feature of orebody,ore characters,characters of petrochemistry composition,REE characters of rocks and ores,and Sm-Nd isotope of Bamianshan fluorite deposit.It shows that Bamianshan fluorite deposit is an unusual large fluorite deposit which was formed mostly by sedimentation and later hydrothermal reformation.Based on the analysis data and combined with characters of ore-hosted rocks and orebody,it is predicted that the sedimentary rocks of Cambrain System as its source bed,which supplied necessary materials of Bamianshan fluorite deposit.Magmatism in later stage altered some orebodies in different extent and formed partial deep lean vein ore bodies in structure belt.