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西维多利亚斯坦韦尔Magdala矿床的金矿化产于该区中绿片岩相浊积岩和海底火山碎屑变质岩中发育的两条剪切带中。形成时间较晚的Scotchmans断裂带叠加在较早的中央矿脉群上。中央矿脉的构造和页理均重新定向,与Scotchmans断裂带平行。纹层状的含金石英脉发育于Scotchmans断裂带的边界主断层中。上盘主断层和下盘主断层之间由一系列呈不规则排列的次级断裂相连接,其中可观察到由擦痕线、旋转剪切叶理和S-C组构组成的复式(duplex)构造。在主断层和次级断裂中均发育断层角砾岩,亦可见到断层泥,表明断层曾多次活动。纹层状石英脉的金含量为4×10~(-6)—5×10~(-6),但是,在它与主次断裂的交汇处,金品位可增高到10×10~(-6)或更高。 有两种矿物组合,一种为早期形成不含金矿化磁黄铁矿-黄铁矿-黄铜矿-方沿矿组合,这些均经历了后期的剪切作用;另一种为含金矿化的产于纹层状石英脉中的黄铁矿-毒砂-黄铜矿组合。矿物金主要呈包裹体金或裂隙金产于黄铁矿和毒砂中。
The gold mineralization at the Magdala deposit in Steinwell, West Victoria, is found in two shear zones developed in the metaplinitic turbidites and submarine volcaniclastic metamorphic rocks in the area. The late-forming Scotchmans fault zone superimposed on earlier central veins. The structure and orientation of the central veins are redirected parallel to the Scotchmans fault zone. The lamellar auriferous quartz veins develop in the boundary faults of the Scotchmans fault zone. The upper plate main fault and the lower plate main fault are connected by a series of secondary faults that are irregularly arranged, in which a duplex structure consisting of a scoring line, a rotating shear blade and an SC structure can be observed . The fault breccias are also developed in the main fault and the secondary faults, and fault muds can also be seen, indicating that the fault has repeatedly moved. The gold content of stratoid quartz veins is 4 × 10 -6 -6 -5 -5 10 -6, however, the gold grade can be increased up to 10 × 10 ~ (-6) at the junction of primary and secondary faults, 6) or higher. There are two kinds of mineral assemblages, one is the early formation of gold-free pyrrhotite pyrite - chalcopyrite - side along the ore combination, which have experienced the later shearing; the other is gold Mineralized pyrite - arsenopyrite - chalcopyrite assemblage in laminar quartz veins. The main gold mineral inclusions gold or fractured gold in pyrite and arsenopyrite.