湖南省崇阳坪地区寨溪山钨矿床围岩蚀变与矿化规律研究

Regularity of Wall Rock Alteration and Mineralization in the Zhaixishan Deposit,Chongyangping,Hunan

湖南崇阳坪地区寨溪山钨矿床属于中型石英脉型白钨矿床。矿区内围岩蚀变作用强烈,蚀变分带明显,依据蚀变岩岩相学及岩石化学测试结果,并结合钻孔编录资料,将矿区围岩蚀变划分为3种类型的蚀变带:(1)电气石化→钾长石化→云英岩化→花岗岩;(2)电气石化→硅化→云英岩化→钾长石化边→花岗岩;(3)硅化花岗岩→花岗岩。钨矿化主要赋存在钾长石化、电气石化、云英岩化蚀变花岗岩中。蚀变带物质组分迁移结果表明,在蚀变过程中,主量元素除Ti O2、Mn O、Mg O外,其他元素迁移量发生了明显的改变,尤其是Si O2、Al2O3、K2O、B等元素富集或亏损明显,W在钾长石化、电气石化蚀变花岗岩中富集明显。

The Zhaixishan scheelite ore deposit is a medium quartz vein-type scheelite deposit, which has an intense wall rock alteration and zoning evidently. According to petrography and petrochemistry of alterated rocks, combining with the data of drill hole, three type alteration zones： tourmaline → potash fossil → cloudsite → granite; tourmaline→ silicification → cloudsite → potash fossil edge → granite; silicification→ granite are identified. Scheelite mineralization mainly occurs in tourmalinization sericitization potassic feldspathization granite. The results of migration quality of components in different alteration zones showed that variation of migration quality in the alteration process is high for the major elements except TiO2、MnO、MgO, Especially SiO2, Al2O3, K2O, B and other elements enrichment or loss is obvious, and W is rapidly enriched in potassic feldsparthization tourmalization granite.