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引言许多太古代矿床部产在太古代绿岩带中或与其紧密共生,这些矿床看来直接源自地幔。世界上一些大型镍、金、银、铜和铬矿床的生成,是与太古代绿岩的火山作用有关的。与太古代火山岩有关的矿床的最明显特征,是它们在空间和时间上完全相似性(从38亿年—26亿年)。Goodwin(1966—1971)提出一个太古代大陆生长模式,其中单一的金-银、镍-铜和铁矿床主要产在岩性上简单而可能比较老的绿岩带中,而复杂的矿产组合,例如Cu-Zn、Ni-Cu、Au-Ag、Fe和其他等,是岩性上多样而可能较年轻的岩带的特征。太古代型式的矿化,看来在26亿年时世界性岩浆事件以后已迅速减弱。在一些大陆
INTRODUCTION Many Archean deposits originate in or closely to Archean greenstone belts, and these deposits appear to originate directly from the mantle. The generation of some of the world’s large nickel, gold, silver, copper and chromium deposits is related to the volcanism of the Archean greenstone. The most striking feature of deposits related to Archean volcanic rocks is their complete similarity in space and time (from 3.8 to 2.6 billion years). Goodwin (1966-1971) proposed an Archean continent growth model in which a single gold-silver, nickel-copper and iron deposit is predominantly produced in lithologically simple and possibly older greenstone belts, while complex mineral assemblages , Such as Cu-Zn, Ni-Cu, Au-Ag, Fe and others, are characteristic of lithologically diverse and possibly younger rock belts. Archean mineralization appears to have rapidly diminished since the worldwide magma event of 2.6 billion years. In some continents