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新西兰北岛科罗曼德尔半岛的火山岩,都是太平洋板块和印度-澳大利亚板块在晚中新世会聚期间形成的。由于俯冲板块边缘的会聚速度不同,导致发生了17—21Ma和4Ma的张性状态和基底塌陷。可以预料,基底塌陷的区域会出现更多的断裂,因而使晚期岩浆流体更容易渗透。这种区域性富氯化物热泉的分布与上述看法是一致的。最近在陶波火山带附近的布罗德兰兹(奥啥阿基)和怀拉基的地热井沉积物中发现有具经济价值量的金,这表明,以此类推,科罗曼德尔半岛的金也可能是以这种方式搬运的。倘若如此,那么可以预料,金矿化远景也会以类似于热泉氯化物含量那种区域性变化的方式为转移。由此看来,科罗曼德尔半岛最北部的金矿化程度可能比南部的要高得多,尽管迄今为止大多数正在开采的大金矿都在南部。
Volcanic rocks in the Coromandel peninsula on the North Island of New Zealand were formed during the Late Miocene after the convergence of the Pacific and Indo-Australian plates. Because of the convergence speed of the subducting plate edges, the tension state of 17-21Ma and 4Ma and the substrate collapse occurred. It is expected that more fractures will occur in the area where the substrate collapses, thus making the late magmatic fluids more permeable. The distribution of such regional chloride-rich springs coincides with the above observations. The recent discovery of economically valuable gold in the geothermal well deposits of Broadlands (Oshawa) and Wairaki near the Taupo volcano suggests that, by analogy, gold from the Coromandel Peninsula may also It is handled this way. If so, it is to be expected that the gold mineralization vision will also be shifted in a manner similar to the regional variation of chloride content in hot springs. In view of this, the gold mineralization in the northernmost part of the Coromandel Peninsula may be much higher than in the south, although most of the large gold mined now is in the south.