A Comparative Ore-Geochemistry of the Geologic Terrains in Japan

洋流在成矿中的作用：过渡元素分布的比较地球化学研究河原义一摘要：为了验证PUMOS假说，我们试图计算出一些典型矿床和海洋沉积物中过渡元素的PUMOS归一化相对丰度。来自世界各地海底的锰结核与来自日本绿凝灰岩地区的黑子矿石在成分模式上具有良好的对称关系。在绿色凝灰岩地区，高度氧化的远洋沉积物与相对还原的页岩之间也存在着本质上相似的关系。另一方面，产于日本古生代至中生代建造中的别石型矿石与层状锰矿之间存在着另一种不同于所观察到的锰结核与黑子矿之间的关系。值得注意的是，Besshi类型的矿石在成分模式上与挪威Framvaren缺氧峡湾的框状黄铁矿相似，并将锰矿层状分布于日本海西南缘的弱氧化褐泥中。这些发现表明，自然界中的矿床在地球化学上等同于海洋沉积物中的硫化物和氧化物部分，从而有力地证明了它们主要是由从海洋中移出的含金属沉淀颗粒(即PUMOS)的氧化还原分馏形成的。

Role of Ocean-Flux in Metallogeny : A Comparative Geochemical Study on the Distribution of Transition Elementsby Yoshimichi Kajiwara Abstract : In order to test the PUMOS hypothesis, an attempt has been made to figure out PUMOS-normalized relative abundances of transition elements in some representative ore deposits and marine sediments. A beautiful symmetric relationship in compositional pattern is observed between Manganese Nodule from the world-wide ocean floor and Kuroko Ore from the Green Tuff region of Japan. Essentially similar relationship is also found between the highly-oxidized pelagic sediments and the relatively reduced shales in the Green Tuff region. On the other hand, between Besshi-Type Ore and Bedded Manganese Ore occurring in the Paleozoic to Mesozoic formations in Japan exists another relationship which is different from what is observed between Manganese Nodule and Kuroko Ore. It is interesting to note that Besshi- Type Ore is similar in compositional pattern to the framboidal pyrite from the Framvaren anoxic fjord in Norway and Bedded Manganese Ore to the weakly-oxidized brownish mud from the southwestern margin of Japan Sea. These findings would indicate that the ore deposits in nature are geochemically equivalent to sulfide and oxide fractions in the marine sediments, and thus strongly evidence that they are essentially originated primarily by the redox fractionation of metalliferous settling particulates which are removed from the ocean (i. e. PUMOS).