云南省永善县务基磷矿床地质特征及成因分析

Geological characteristics and genetic analysis of Wuji phosphorite deposit in Yongshan county,Yunnan province

云南省永善县务基磷矿赋存于下寒武统梅树村组中谊村段地层中,矿石矿物以胶磷灰石为主,具砂屑、砾屑及鲕粒结构,薄-中层状、块状及条纹条带状构造,矿石自然类型为砾屑状磷块岩、条纹状白云质磷块岩、条带状白云质磷块岩、硅质磷块岩。通过分析矿区所处古构造、古地理特征和矿石结构特征,认为务基矿区磷矿为浅海相沉积磷块岩矿床。

Wuji Phosphate mining area in Yongshan County,Yunnan Province is located in the northwest of Suijiang-Yongshan-Zhaotong phosphorous forming zone of Xiaotan-Yangchang phosphorous accumulating basin.Wuji phosphate deposits occurs in the Zhongyicun section of the lower Cambrian Meishucun formation.Ore minerals are mainly colloidal apatite,with sand debris,gravel debris and oolitic structure,thin-medium layered,massive and striped or banded structure.The natural types of the ores are gravelly phosphorite,striped dolomitic phosphorite,banded dolomitic phosphorite and siliceous phosphorite.By analyzing the paleostructure,paleogeography and ore structure features of the mining area,it is considered that the phosphate deposit in Wuji mining area is a shallow marine sedimentary phosphorite deposit.