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人们认为含铁沉积物有以下两种类型:1.通过化学沉淀形成的铁建造主要由薄层燧石条带和铁矿物所组成;2.含有相当数量的粘士和碎屑成份,通常由鲕绿泥石—菱铁矿—针铁矿组成的泥铁矿层。这两种类型都是在大范围的沉积环境中形成的,并且都具有各自不同的岩相和矿物相。硅质铁建造依其沉积盆地的特征以及伴生岩石的种类可分成两种主要类型即苏必利尔湖型和阿尔戈马型。其中,苏必利尔湖型是:在大陆架环境中,沉积有石英岩、白云岩和黑色页岩;而阿尔戈马型则是:沿着火山弧,断裂带以及深成断层和破裂系,沉积有火山岩和硬砂岩的组合。与铁建造中铁和硅化学沉淀的沉积环境分类有关的因素有:浅海环境、大陆架环境和深海盆地环境;靠近火山中心的断裂带和断层系;伴生沉积物和火山岩的类型;矿物学、沉积特征和铁建造岩相。
There are two types of iron deposits considered to be: 1. Iron formed by chemical precipitation is mainly composed of thin-layer flint bands and iron minerals; 2. contains a considerable amount of viscous and detritus components, usually Ophiolite - siderite - goethite. Both types are formed in a wide range of depositional environments and have different lithofacies and mineral phases. The construction of siliceous iron can be divided into two main types, the Lake Superior and the Algoma, according to the characteristics of its sedimentary basin and the types of associated rocks. Among them, the Lake Superior type is: In the continental shelf environment, quartzite, dolomite and black shale are deposited, while the Argoma type is: along volcanic arcs, fault zones, deep faults and ruptures, A combination of volcanic and hard sandstone. Factors related to the classification of sedimentary environments for iron and silicon chemical precipitation of iron: shallow sea environment, shelf environment and deep-sea basin environment; fault zones and fault systems near volcanic centers; associated sediments and volcanic rocks; mineralogical and sedimentary characteristics And the iron building facies.