云南省鹤庆锰矿区地质特征与找矿标志探讨

A Discussion on Geological Characteristics and Prospecting Indicators of Heqing Manganese Mine Area in Yunnan Province

锰矿受地层岩性控制,产于含锰地层海相硅质—碳酸盐岩中,含锰岩系为一套含炭质粉砂质页岩、炭质页岩、菱锰矿、白云岩、凝灰质粘土岩所组成;含锰矿层矿石主要由硬锰矿、软锰矿、偏锰酸矿组成。含锰岩系风化后常形成红土、黄棕土或黑褐土,含有像绿豆、黄豆般大小的浑圆状锰粒的红土,或含有锰矿碎屑的黑褐土,可作为寻找风化锰矿床的重要标志。含锰矿层围岩一般岩性较坚硬、分布稳定,锰矿多分布于向斜两翼的浅部,地下水面以上的氧化带内。淋积型锰多分布构造破碎带内,堆积型锰矿产于第四系红土层中;白云岩透镜体出现的地方,常伴随具有工业品位的锰矿体出现。许多热水成因的矿床附近都会有白云岩透镜体出现。

Manganese ore is controlled by stratum lithology and occurs in marine siliceous-carbonate rocks of manganese-bearing strata.The manganese-bearing rock series are composed by a set of carbonaceous silty shale,carbonaceous shale,rhodochrosite,dolomite and tuffaceous clay rocks.The manganese-bearing ore beds are mainly composed of hard manganese ore,pyrolusite and metamanganic acid ore.After weathering,the manganese-bearing rock series often forms laterite,yellow brown soil or black cinnamon soil,which contains mungbean-like clay.Soybean-sized rounded manganese laterite,or black cinnamon soil containing manganese ore debris,it can be used as an important indicator for the search for weathered manganese deposits.The surrounding rock of manganese-bearing ore beds is generally hard and stable in distribution.Manganese ore is mainly distributed in the shallow part of the syncline wings and in the oxidation zone of the surface of groundwater.It accumulates manganese minerals that occur in the Quaternary laterite strata in the eluvial manganese multi-distributed structural fractured zone.Where dolomite lenses appear,they are often accompanied by manganese ore bodies of industrial value.There are many dolomite lenses nearby deposits of hydrothermal origin.