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Shiroishi Pass

Ikenohara, Doshi city, Minami-Tsuru county, Yamanashi pref., Japan

Occurrence

I-type (Magnetite-series) skarn

Crystalline limestone formed by Albite-Epidote-hornfels facies contact metamorphism of the late Miocene (7 Ma) Tanzawa tonalite intruded in the early Miocene (17 Ma) Togatake Subgroup, the bottom member of Tanzawa Group. The Tanzawa Group is considered as the accreted Izu island arc. The Tanzawa tonalite is I-type (Magnetite-series). Approximately 1 km apart from tonalite, the heat source. Ages of sedimentary rocks were determined by microfossils, tonalite by radiometric dating.

Shiroishi Pass

Outcrop of crystalline limestone in the Togatake Subgroup. This outcrop is composed of white crystallized limestone, marble. The black part on the surface is dirt. This crystalline limestone contains few impurity minerals.

Reported Minerals

  • Calcite

Mineral Assemblages

  • Calcite
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