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导言 含铁建造从最古老的前寒武纪至近代都有出现,但前寒武纪条带状含铁建造在其规模和组成上都具有恃殊的意义。它们基本上是由硅和铁构成,仅带有少量或微量的其他元素。 硅的来源以及沉积和搬运的形式是一个至今尚未取得一致意见的老问题。许多地质学家认为条带状含铁建造在中前寒武纪或下元古代,即2600至1800百万年前显著发育。然而类似的沉积通常是在较老的前寒
Introduction Iron-bearing constructions have emerged from the ancient Precambrian to modern times, but the Precambrian banded iron construction is of special significance in terms of its size and composition. They consist essentially of silicon and iron, with only minor or minor amounts of other elements. The source of silicon and the forms of deposition and handling are old issues that have so far not been agreed upon. Many geologists believe that banded iron was built predominantly in the Middle Precambrian or the Lower Proterozoic, 2600-1800 million years ago. However, similar deposits are usually older cold