Fromation mechanism and origin of gold-silver deposits in Japan

日本金银脉型矿床可分为浅成热液型和低温/中温热液型两种类型。通过对矿石和脉石矿物、流体包裹体、围岩蚀变和稳定同位素的研究，估算了浅成热液型和低温/中温热液型金银脉型矿床的化学环境和成因。差异是针对这两种类型的这些特征进行了澄清。将这两种类型的这些特征与其他类型（黑子型、矽卡岩型）进行了比较。这一比较表明，这些矿床可分为两种类型：富硫化物矿床和贫硫化物矿床。富硫化物矿床形成于比贫硫化物矿床更浅的环境中。

Gold-silver vein-type deposits in Japan can be divided into two types;epithermal-type and hypo/mesothermal type.Chemical environments and origins for epithermal and hypo/mesothermal types were estimated based on the studies of ore and gangue minerals, fluid inclusions,wall rock alteration and stable isotopes. Differences is these characteristic features for these two types were clarified. These characteristic features for these two types were compared with those for the other types (Kuroko-type, Skarn-type). This comparison suggests that these deposits can be divided into two types, sulfide-rich and sulfide-poor deposits. Sulfide-rich deposits were formed under the shallower environment than sulfide-poor deposits.