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文中报导了冰岛东部第三系玄武熔岩和脉岩中的金含量。在不饱和(橄榄石标准矿物)拉斑玄武岩中,金含量随分异程度而降低。但在饱和(石英标准矿物)和分异较强的岩石中,金显示出与不相容元素如Y和Zr呈高度的正相关。这种性状表明,在晚期岩石中,金不保存在早期的结晶相中而富集在残余熔体中,所以,它遵循了不相容元素的趋势。因此玄武安山岩和富硅冰岛岩含有两倍干玄武岩的金(x=4.1ng/g)。这种总的趋向似乎与硫在岩石中的不规则伴生富集有关。氧化作用和沸石化作用导致了金在火山碎屑单元和熔岩流孔洞顶部的富集。这表明,在冰岛型火山堆积序列中,最适用于金矿化的源岩可能是演亿较强烈的石英——标准矿物拉斑玄武岩(铁玄武岩)、玄武安山岩和冰岛岩,特别是脉岩和火山碎屑岩单元。固结不紧的金由于风化作用、深埋变质作用和热液蚀变作用容易从火山玻璃和硫化物中迁移出。因此,只有最新鲜的玻璃质岩石才可能保留着原始的金含量。
The paper reports the gold content of Tertiary basalts and vein rocks in eastern Iceland. In unsaturated (olivine standard) tholeiite basalts, the gold content decreases with the degree of differentiation. However, gold shows a high degree of positive correlation with incompatible elements such as Y and Zr in saturated (quartz standard minerals) and highly differentiated rocks. This trait shows that in late rocks, gold does not accumulate in the early crystalline phases and accumulates in the residual melt, so it follows the trend of incompatible elements. Basaltic Andesite and Silica-rich Icelandic gold thus contain twice as much gold as dry basalt (x = 4.1 ng / g). This general trend appears to be related to the irregular associated enrichment of sulfur in rocks. Oxidation and zeolitization lead to the enrichment of gold at the top of volcaniclastic units and lava flows. This indicates that the most suitable source for gold mineralization in the Icelandic volcanic accumulation sequence may be the quartz -standard mineralitic basalt (iron basalt), basaltic andesite and Icelandic rocks, and especially the veins And pyroclastic units. The tight consolidation of gold due to weathering, deep metamorphism and hydrothermal alteration easily migrated from volcanic glass and sulfide. Therefore, only the freshest vitreous rock retains its original gold content.