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昆士兰州西北部的艾萨山镇硫化物矿床,产在已变质成低级绿片岩相的,并在热液活动影响下发生不同程度蚀变的粉砂岩—页岩层序中。形成铅—锌—银矿体的方铅矿和闪锌矿以及细粒黄铁矿,与这些沉积物成互层;而黄铜矿矿化看来已迭加于其上。在最大的矿体-1100矿体中,有一个高品位的块状黄铜矿核,产在黄铁矿矿化强烈的同一层位上;这个核随着黄铁矿的富集而缩小。钴矿物与黄铜矿矿石密切伴生,并表现出与上述情况相同的关系。黄铜矿与黄铁矿的硫同位素值的变化范围相同,表明硫的来源是共同的。黄铁矿层中硫的丰度,并不随着铜品位的增长而增加。这些因素证实组成黄铜矿和富钴硫化物所必需的硫,来自先存地层层序的观点。硫的这种来源,控制了铜、二氧化硅和钴从矿化溶液中的沉积,并为解释铜与铅—锌—银矿石的空间关系提供了联系。
The Isaan Town sulfide deposit in northwestern Queensland is produced in a siltstone-shale sequence that has been altered into low-grade greenschist facies with varying degrees of alteration under hydrothermal activity. Galena and sphalerite, as well as fine-grained pyrite, forming a lead-zinc-silver ore body interbedded with these deposits; chalcopyrite mineralization appears to have superimposed on it. In the largest ore body -1100 ore body, there is a high-grade massive chalcopyrite core, produced in the pyrite mineralization in the same layer; this nucleus with pyrite enrichment and reduced. The cobalt mineral is closely associated with the chalcopyrite ore and shows the same relationship as the above. The sulfur isotope values for chalcopyrite and pyrite range from the same, indicating that the sources of sulfur are common. The abundance of sulfur in pyrite does not increase with increasing copper grade. These factors confirm the sulfur necessary for the formation of chalcopyrite and cobalt-rich sulfides from the viewpoint of pre-stratigraphic sequence. This source of sulfur, which controls the deposition of copper, silica, and cobalt from mineralized solutions, provides a link to explain the spatial relationship between copper and lead-zinc-silver ores.