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克尔艾迪生——阿伯蒂比带中的一个大型太古代脉金矿床,位于紧靠区域性构造破裂——柯克兰莱克-拉尔德莱克断层带南面的一个滑石-碳酸盐和绿泥石-碳酸盐岩带中。残余的火山结构连同活动性比较低的特征元素的比值表明,矿体的围岩原来大多是镁铁质和超镁铁质岩石及其派生的碎屑岩。 CO_2与碱金属饱和指数移动平均值的投影与金丰度变化的惊人一致,说明金的富集作用与热液蚀变有成因联系。就大范围来说,金富集在柯克兰莱克-拉尔德莱克断层带以南,就细部来说,富集在碳酸盐-白云母型蚀变和碳酸盐-钠长石型蚀变之间的过渡带中。 金富集在柯克兰莱克断层带的一侧被认为是由氧化态梯度变化产生的交代分带所造成的,贵金属富集在还原的一侧。柯克兰莱克-拉尔德莱克断层带南面的蚀变类型分带代表了与外生流体的成分相适应的、连续而逐渐加深的岩石变化过程的不同阶段。连续产生的断裂组合和矿脉有着相同的蚀变型式,因此,流入的热液流体的成分看来在整个时期中基本上没有发生变化。 克尔艾迪生矿山的金矿化及其邻近的蚀变晕被解释为周期性出现的水力压裂、流体渗透及其与岩石的局部反应所造成的结果。流体-岩石的相互作用使流体的成分发生了侧向变化,导致了金的富集(这可能是由于pH值梯度变化的缘故),使金优先富集在?
A large Archean vein gold deposit in the Kerd Addison-Abertish Belt, located in the immediate vicinity of the regional tectonic fracture - a talc-carbonate and chlorophyll south of the Kirkcudrek-Lal-Drake fault zone Stone - carbonate belt. The ratio of the remaining volcanic structures, together with the less active feature elements, indicates that most of the surrounding rock in the ore body was originally mafic and ultramafic rocks and their derived clastic rocks. The projection of the moving average of CO_2 and the saturation index of alkali metals is surprisingly consistent with the change of gold abundance, indicating that the enrichment of gold has a causal relationship with hydrothermal alteration. On a large scale, the gold enrichment is south of the Kirkland Lake-Lal-Drake fault zone and, in detail, is enriched in carbonate-muscovite alteration and carbonate-albite alteration In the transition zone between. The enrichment of gold on the Kirkland Lake fault zone is believed to have been caused by the metasomatic zonation associated with a gradient of oxidation states, with the enrichment of precious metals on the reduction side. The alteration-type zonation south of the Kirkland-Lakeland Lake fault zone represents different stages of rock formation that are continuous and progressively deepened to suit the composition of exogenous fluids. The succession of fractured assemblages have the same alteration pattern as the veins, so the composition of the inflowing hydrothermal fluid does not appear to substantially change throughout the period. Gold mineralization in the Kerd Addison Mine and its adjacent erosional halo are interpreted as a result of cyclical hydraulic fractures, fluid infiltration, and their local reactions with rocks. The fluid-rock interaction changes the composition of the fluid laterally, resulting in the enrichment of gold (which may be due to a change in the pH gradient), allowing gold to be preferentially enriched in?