At the Chitose mine, subvolcanic hydrothermal Au-Ag quartz veins occur in a propylitic volcanic complex. The emplacement of the deposits is controlled by fractures arranged en echelon fashion in the upper level and in cymoid loop in the middle. The deposits grade to simple veins in the lower level.
The flow directions of ore solution which produced the Fukujinzawa and Maizuru deposits were deduced by the analysis of the assay patterns.