黔东北黑色泥岩盆地含锰岩系的铁锰地球化学特征  

Geochemical Characteristics of Manganese Bearing Rock Series in Black Shale Basins of Northeast Guizhou,China

作　　者：潘文[1] 禚喜准[2] 陈骁帅 杨胜堂[3] 赵爽[3] 

机构地区：[1]中国地质大学(武汉)地球科学学院,武汉430074 [2]辽宁工程技术大学地质系,辽宁阜新123000 [3]贵州省地质矿产勘查开发局103地质队,贵州铜仁554300

出　　处：《沉积学报》2016年第5期868-880,共13页Acta Sedimentologica Sinica

基　　金：国家自然科学基金(41402101);中国地质调查区域地质调查项目(121201010000150011-12)~~

摘　　要：黑色泥岩盆地内的菱锰矿矿床中常伴生大量黄铁矿,由于菱锰矿和黄铁矿的沉积过程难以直接观察,铁锰的富集关系尚不明确。为了探讨二者的相互关系,以黔东北西溪堡锰矿的典型剖面为例,根据岩石薄片、TOC分析和元素分析等手段,分析了含锰岩系及其顶底板的岩性序列、矿物组合和铁锰地球化学特征,与现代沉积的菱锰矿进行了对比分析。研究表明,在黄铁矿和菱锰矿富集关系上,西溪堡锰矿与现代波罗的海具有类似特征。含锰岩系顶板和底板的锰含量较低;含锰岩系内部的Mn含量波动很大,与铁含量呈负相关。黄铁矿和菱锰矿的沉淀析出具有先后顺序,通常黄铁矿从溶液中析出在先,菱锰矿沉淀在后。The rhodochrosite ores in black shale basins are usually occupied by a large quantity ol pyrites, cause the deposit processes ol rhodochrosite and pyrite are hard to observe directly, the enrichment relationship ol them is not clear currently. To study the correlation between them, this research selected typical profile ol Xixibao manganese ore in northeast ol Guizhou province as example. It is based on ordinary thin section, TOC analyses and elemental analyses ,which analyzed lithological sequence, mineral assemblage and the geochemical characteristics ol Mn and Fe in the manganese-bearing rock series and the rool and lloor ol them, and at the same time carried out comparison analyses with modern rhodochrosite deposit. Reaearch showed that the Xixibao manganese ore did share some similar characteristics with that ol modern Baltics Sea on the enrichment relationship ol pyrite and rhodochrosite. The Mn content is low in both rool and lloor ol the manganese-bearing rock series; inner the manganese-bearing rock series the Mn content lluctuated greatly and is negatively correlated with the Fe content. The precipitation ol pyrite and rhodochrosite has a sequence, usually the pyrites are precipitated lirst lrom the solution and lollowed by rhodochrosite.

关 键 词：大塘坡组 菱锰矿 黄铁矿 Mn/Fe比 沉积分异 

分 类 号：P618.3[天文地球—矿床学]