Hishikari mine

Figure 1.8. Schematic northwest-trending section across the Main and the Sanjin deposits of Hishikari mine (Ibaraki and Suzuki, 1993).

Figure 1.104. The relationship among S O (in permil) of fluids, minor element contents, and A/Q (adula-ria/quartz ratio) in the vein from wall rock side (3-IT) to central part (5-2T) (Ryosen No. 5 vein, Hishikari mine, 85 ml E50) (Shikazono and Nagayama, 1993).

Shikazono et al. (2002) considered the depositional mechanism of quartz and cristobalite and the change in silica concentration of fluid migrating through the altered rocks in the Hishikari mine district based on kinetics-fluid flow mixing model. Their discussion is summarized below. 

Abe, I., Suzuki, H., Isogami, A. and Goto, T. (1986) Geology and development of the Hishikari mine. Mining Geology, 36, 117-130 (in Japanese with English abst.). 

MMAJ (Metal Mining Agency of Japan) and SMM (1987) Discovery and development of Hishikari mine. Mining Geology, 37, 227-236 (in Japanese). 

Takahashi, M. Ishiyama, T. and Mizuta, T. (1998) Structure and environment of formation of the Hosen No. 5 and Ryosen No. 5 gold-quartz veins, Hishikari mine. Japan. Rep. Inst. Appl. Earth Sci. Dep. Geosci. Akita U., 63, 55-72 (in Japanese with English abst.). 

The coupled precipitation kinetics-fluid flow model was applied to the distribution of Si02 content and K2O content of the hydrothermally altered andesite in the Hishikari Au-Ag mine area, south Kyushu, Japan by Shikazono et al. (2002). This will be described in section 1.4.6. 

Sedimentary rocks often occur as host rocks, footwall rocks and basement rocks in the Non-Green tuff mine area. For example, in southern Kyushu, the Shimanto Supergroup shale is dominant as basement and a host rock for epithermal Au-Ag vein-type deposits (e.g., Hishikari). 

Izawa et al. (1990) recognized the following alteration zones from the vein towards margin of the Hishikari Au-Ag mine area, chlorite-sericite zone (zone IV), interstratified clay mineral zone (zone III), quartz-smectite zone (zone II) and cristobalite-smectite zone (zone I) and least altered zone (L.A. (least altered) zone) (Fig. 1.131). 

Ibaraki, K. and Suzuki, R, (1990) Wall rock alteration in the Hishikari gold mine, Kagoshima Prefecture, Japan. Mining Geology, 40, 97-106 (in Japanese with English abst.). 

Ibaraki, K. and Suzuki, R. (1993) Gold-silver quartz-adularia veins of the Main, Yamada and Sanjin deposits, Hishikari gold mine a comparative study of their geology and ore deposits. Resource Geology Special Issue, 14, 1-11. 

Ishihara, S., Sakamaki, Y., Sasaki, A., Teraoka, Y. and Terashima, S. (1986) Role of the basement in the genesis of the Hishikari gold-quartz vein deposit, southern Kyushu. Japan. Mining Geology, 36, 495-510. 

Urashima, Y. and Izawa, E. (1983) Ore of the Hishikari deposit from the boring core. Mining Geology, 33, 50 (in Japanese). 

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