广西德保县荣华锰矿床地质特征研究

Geological characteristics of the Ronghua manganese deposit in Debao County,Guangxi

荣华锰矿赋存于桂西三叠系百逢组中,为该层位首次发现的中型规模锰矿。笔者通过参与矿区锰矿勘查工作,采用室内外观测、测试、工程揭露和验证等手段,对研究区地层、构造、沉积演化、含矿层位、矿体及矿石矿物特征、矿床成因和找矿标志等方面进行了分析探讨。研究发现荣华锰矿为典型的沉积-锰帽型矿床,严格受地层和构造因素控制;矿石类型主要为氧化锰矿贫锰矿石;氧化锰矿物主要为水羟锰矿、硬锰矿及软锰矿;矿床成因与原始沉积作用、后期风化淋滤等有重要关系;百逢组浊积岩之下、罗楼组碳酸盐岩之上的狭窄范围是荣华锰矿的典型找矿标志,该标志对大量出露三叠系百逢组的桂西地区具有普遍意义,同时指出桂西地区该组地层内具有良好的找矿前景。

Located in the Middle Triassic Baifeng Formation of Western Guangxi,the Ronghua manganese deposit is the first economic Mn deposit discovered in Baifeng Formation.Based on geological exploration,laboratory analysis,testing and engineering work,the authors studied the ore deposit in such aspects as strata,structure,sedimentary evolution,ore-bearing horizon,ore body and ore characteristics,genesis and prospecting criteria and,on such a basis,reached the conclusion that the Ronghua manganese deposit is a typical sedimentarymanganese hat deposit,strictly controlled by strata and structure.The main types of manganese minerals include vemadite,psilomelane and pyrolusite.The formation of the ore deposit was mainly related to original sedimentation,weathering and leaching.There exists good prospecting potential between the turbidite of Baifeng Formation and the carbonate rock of Luolou Formation.The strata of the Baifeng Formation are widely exposed in western Guangxi.These typical prospecting criteria may contribute to finding new manganese deposits and have a universal meaning.