General overview of metallogeny and tectonics in the Japanese Islands

General overview of metallogeny and tectonics in the Japanese Islands 

Before mentioning the characteristics of Kuroko and epithermal vein-type deposits in Japan, it is worthwhile to briefly describe the metallogeny, geology, geophysics, and tectonic situations of the Japanese Islands. 

Japan is situated along the boundary between Eurasia and the Pacific plate (Fig. 1.1). The metallogeny, geology, geophysics and geochemistry of Japan are largely controlled by this tectonic setting. 

The great variety of mineral deposits of Japan reflects the complex geotectonic environments. An intimate relationship exists between igneous and hydrothermal activity, which in turn reflects the plate tectonic history of Japan. Many Japanese ore deposits have produced many different metals, and they contain almost all common and useful minerals, although many deposits are small in size. 

Important metallic ore deposits include Besshi (Kieslager)-type (strata-bound cupriferous pyritic deposits), strata-bound Mn-Fe-type, skam-type, Kuroko-type and vein-type. Dominant non-metallic deposits are limestone, clay, native sulfur, zeolite, silica and gypsum deposits. The deposits are divisible into three groups, based on their ages of formation Carboniferous-Jurassic, Cretaceous-Paleogene and Tertiary-present. 

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