条带状铁建造(BIFs)研究的几个问题

前寒武纪条带状铁建造(BIFs)中拥有全球最重要的铁矿资源,BIFs中以及包括BIFs在内的含铁岩系还含有丰富的金、铜、锌、钴、铂族等有用元素。本论文主要针对BIFs形成过程中与成矿有关的几个关键问题进行评述和探讨,包括BIFs的成矿系列,地幔柱与BIFs的关系,微生物在BIFs形成中的作用等。认为BIFs内部以及包括BIFs在内的含铁岩系均构成贱、贵金属成矿系列;地幔柱与BIFs之间存在密切的时、空和成因联系;在早前寒武纪缺氧的环境下,厌氧的细菌类生物通过光合作用为BIFs中铁质沉淀提供了氧。希望该研究对包括BIFs的成矿作用在内的前寒武纪地质研究以及拓展找矿思路有所启示。

SEVERAL PROBLEMS INVOLVED IN THE STUDY OF BANDED IRON FORMATIONS (BIFs)

It was thought that the most important Fe sources occur in Precambrian BIFs.BIFs and ferruginous rock series in them contain abundant usable Au,Cu,Zn,Co and PGEs elements.Some key problems,which were related with metallogenesis during BIFs-forming process,were discussed by the authors,i.e.,the metallogenic series of BIFs,relationships of mantle plume and BIFs,and microorganic function in the BIFs process,etc.It was concluded that a noble and base metal metallogenic series was composed of the inner part of BIFs and ferruginous rock series.And mantle plume had close spatio-temporal and genetic relationships with BIFs.In anoxic environment in Precambrian,the anaerobic bacteria would provide oxygen for ferruginous deposition during photosynthesis.It may promote the study of Precambrian geology and development of ore-prospecting ideas,which are related with BIFs metallogenesis.