福建省清流县仁场锰矿地质特征及其成因探讨

Geological Characteristics and Genesis of the Renchang Manganese Deposit in Qingliu County, Fujian Province

摘要福建省清流仁场锰矿位于闽西南坳陷带的中部、次级构造明溪胡坊-永定水下隆起带的西侧。含锰岩系在构造作用下逆冲于二叠系下统文笔声山组地层之上。含锰岩系在矿区为一套硅质岩、粉砂质泥岩的潮坪相沉积。矿体呈层状,产状与含锰岩系地层一致。矿石矿物主要为钡镁锰矿、隐钾锰矿和软锰矿。脉石矿物主要为石类、水云母。矿石呈隐晶一微晶结构,块状、土状构造。矿石类型主要为氧化富锰矿石。矿石成因类型属氧化带含锰灰岩风化锰帽型。原生含锰层位推测为石炭系中上统,属石炭系中统可能性更大。

The Renchang manganese deposit in Qingliu County, Fujian Province occurs in the central part of the southwestern Fujian geotectogene and in the western side of the Hufang (in Mingxi County)-Shuixia(in Yongding County)mole track. The manganese-bearing rock series in the mining district is a suit of silicalite and silty mudstone of the tidal-flat faces and has a thrust over the Early Permian strata. The manganese orebodies occur as layer and have the same occurrence as the strata of the manganiferous rock series. The ore minerals are mainly todorokite, cryptomelane and pyrolusite, and the gangue minerals quartz and hydromica. The manganese ores have the aphanitic-microcrystal texture and massive and soillike structures. The ore type presents the oxidized manganese-enriched ores. The genetic ore type is the type Of manganese hats weathered from the manganese-bearing limestone in the oxidation zone. Therefore, it is inferred that the protogenetic manganese-bearing strata should be middle-upper carboniferous, most probably middle carboniferous.