摘要
THE Kangdian region is a middle Proterozoic continental rift basin that extends between longitudes 101°30’and 103°20’. There are a series of sedimentary strata, named Xiaoqingshan Formation, Yinmin Forma- tion, and Luoxue Formation. The strata were metamorphosed and deformed in Jinning tectonic event between approximately 850 and 750 Ma. There are many lode-copper deposits in the Kangdian region. Xiaoqingshan is a typical one among of them. The orebodies of the deposit occurs in veins and the hostrocks of the deposit are sericite-phyllite and sericite-slate. The deposit is characterized by large-scale pervasive sodium metasomatism （PSM）. It has been identified that albite replaced sericite and chlorite of the original rocks during the PSM.As a result, the pelites were transformed into albitolite, which consists of albite totally. Mass balancecalculations show that the PSM process involved addition of large amount of Na<sub>2</sub>O and SiO<sub>2</sub>, and
