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马达加斯加位于非洲东部,是世界第四大岛。到目前为止,马达加斯加Maevatanana 地区还没有进行工业化开采金矿床,主要靠手工开采,估计马达加斯加每年的金产量3~4t左右。根据钻孔岩芯化验结果可知,本地区的矿化类型主要为含金石英脉,其次为含金长英质脉。后期的含金石英脉切穿了早期的含金长英质脉,说明该地区具有2期成矿作用。含金长英质脉容矿构造为NNW向剪切带,含金石英脉产在NNW向剪切带和NNE向断层交汇处。 NNE向断层后期活动,破坏了含金石英脉。

Madagascar sits in eastern Africa ,ranking the fourth largest island in the world .To this day ,there is no organised or industrialized gold exploitation in Maevatanana region besides manual mining work .This is a large amount considering that all is presently from artisanal mining of mainly alluvial deposits .The region's estimated gold produc-tion is 3-4 tonnes/year.The Au deposit in the Maevatanana region is a classical quartz vein type gold deposit in the greenstone belt by the results of chemical test of drill cores ,the quartz veins was controlled by faults .The chemical tes-ting of the drill core demonstrates that the gold deposits in the Madagascar mainly comprise gold-bearing quartz veins , subordinating the gold-bearing felsic veins .The late gold-bearing quartz veins crosscut the gold-bearing felsic veins , suggesting that there is two epochs of mineralization in the study area .The gold-bearing felsic veins are hosted by the NNW-trending shear zone ,and the gold-bearing quartz veins is related to the intersection of the NNW-trending shear zone and the NNE-striking faults .The NNE-striking faults reworked and crosscut the gold-bearing quartz veins .

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