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基本特征本文所介绍的矿床类型在地质文献中从未被系统描述过。岛弧型贵金属矿床是中生代火山成因的浅成低温热液金矿床或银矿床,它们与火山岩是同源的。在典型情况下,其特点是后生热液矿床迭置在略早的喷气矿床之上。这些矿床或以金为主,或以银为主,还有部分贱金属副产品。目前已知的九个此类矿床中有六个是银矿,银的平均品位为2.65盎司/吨(90克/吨);其余三个是金矿,金的平均品位接近0.119盎司/吨(4.0克/吨)。与岛弧银矿相比,金矿位于相对于科迪勒拉现代边界更外侧的地带(西侧)。
Basic Features The types of deposits described in this article have never been systematically described in geological literature. Island arc precious metal deposits are epithermal, epithermal hydrothermal gold deposits or silver deposits, which are homologous with volcanic rocks. In the typical case, it is characteristic that the meta-hydrothermal deposit is superimposed on the earlier jet deposit. These deposits are dominated by gold or silver, with some base metal byproducts. Six of the nine such deposits currently known are silver, with an average silver grade of 2.65 oz / t (90 g / t); the remaining three are gold mines with an average gold grade of nearly 0.119 oz / t 4.0 g / tonne). Compared to the Isle of Arc silver deposit, the gold mine is located on the outer side of the modern border with Cordillera (west side).