Compositional Characteristics of Ores and Rare Minerals in the Kieslager-type Deposits of Japan

基斯拉格型矿床与海底基性火山作用有成因联系。矿石矿物学非常简单，主要由黄铁矿、黄铜矿和闪锌矿组成。富铜矿石中方铅矿、碲铁矿和自然金很少出现，富磁黄铁矿矿石中的几种钴矿物是由黄铁矿转化而来的，在柳原日野谷L-1矿体的富锌矿石中，锗含量高达4.3%的辉锑矿与黄铁矿、黄铜矿、黄铁矿和重晶石共生。在与酸性火山作用有关的黑矿中已知有含锗矿物的产出，但在基斯拉格型矿床中不知道。硫<34>矿物的CDT值在Kieslager型矿床中处于+1 ~+7%的狭窄范围内，与现代洋脊硫化物矿床相似。与四国三八川带的沉积物相比，该值似乎在三八川带的四万十带和天龙川地区的沉积物中更大。原因仍然没有解决。需要进一步的同位素研究。

The Kieslager-type deposits are genetically related with submarine basic volcanism. The ores are mineralogically very simple consisting mainly of pyrite, chalcopyrite and sphalerite. Galena, tetratedrite and native gold occur rarely in copper-rich ores, and several kinds of cobalt minerals in pyrrhotite-rich ores converted from pyritic ores.Colusite with up to 4.3 % germanium occurs with bornite, chalcopyrite, pyrite and barite in Zn-rich ores of the Hinotani L-1 orebody, Yanahara mine. The occurrence of Ge-bearing minerals has been known in the Kuroko deposits related genetically with acidic volcanism, but not known in the Kieslagertype deposits. The rhyolitic volcanism in near-continent submarine environments is suggested to be responsible for the ore genesis at Yanahara.The ^<34>S values(CDT)of sulfide minerals including the present data are in a narrow range from +1 to +7 % in the Kieslager-type deposits, similarly to the modern Ridge sulfide deposits. The values seem to be larger in the deposits of the Shimanto belt and of the Tenryu river area in the Sanbagawa belt, compared with the deposits in the Sanbagawa belt in Shikoku. The reason is remained unsolved. Further isotopic study is needed.