Pustaka Ilmiah Universitas Padjadjaran

Abstrak

Epithermal mineralization at the Teine mine, southwestern Hokkaido, Japan

The southwestern district of Hokkaido has produced valuable amounts of gold, silver, lead as well as zinc metals. This significantly accounts for an important portion of the mineral production in Japan. These resources are related with the many Neogene epithermal ore deposits, such as the Teine, Toyoha, Todoroki and Chitose mines in this area. Most of the mines in this district had closed down during the past 30 to 50 years due to the exhaustion of ores including the Teine deposit. The Teine mine had 10.4 ton of Au and 62.6 on of Ag resources with 6.0 Ag/Au ratio. Other metal production produced 7,560 ton of Cu. The mine was in production from 1932 until 1971 (Shikazono et al., 1990). Previous works had been done on the geology, mineralogy, structural geology and metallogeny of the mineralized district as well as on the Teine deposit. Despite these previous studies, the occurrence and associated ore minerals in the Teine deposit is still interesting to study since there are various kinds of ore minerals is present in this deposit. This study attempts to update the association of ore minerals and to clarify the formation conditions of the Teine mine. Determination of ores mineral assemblages is based on the study of samples collected during field works in some deposits around southwestern Hokkaido and from the Hokkaido University Museum collection. A combination of microscopic, electron-microprobe and BSE-based image analyses of polished and doubly polished thin sections