北海道,農羽鉛・亜鉛鉱脈型鉱床における鉱化作用の指示要素

抄録

The Toyoha Vein type Pb-Zn ore deposit occurs in the Neogene Tertiary andesitic volcanics. The studies of geochemistry and alteration on wall rocks revealed that the mineralized zone is indicated by following three anomalies.
·high MnO concentration
·high F concentration
·the lack of plagioclase and calcite.
These anomalies always overlap near the veins on the underground mining levels. On the other hand, only local anomalies are found on the surface, because most of the veins of the Toyoha ore deposit are blind and have no outcrop. For this reason, the relationship between the surface anomalies and the location of blind veins is obscured. This fact im-plies that blind vein does not always exist right under the surface anomaly, and that we should not abandon the circumference area of the anomaly.