[ Top ] [ Japanese ]
Kasuga Volcanic Rocks
Tarugasawa Lava is Mount Yashigamine origin.
- Type locality: Kakuma river, Saku city, Nagano prefecture; Otake river - Mount Yabashirayama - Mount Kengamine, Sakuho city, Minamisaku county, Nagano prefecture
- Volcanic rocks
- early Pleistocene (1.2 - 0.95 Ma)
- Lithofacies: Basalt, Andesite, Dacite
- Lithofacies: Lava (Several dozen flow units), Volcanic breccia, Tuff breccia, Agglomerate, Scoriaceous agglomerate
- Thickness: 700 m
- Eruptive volume: 73.2 km3
- Upper limit: Unconformity (Chojabaru Gravels, Amazakai Pyroclastic Flow Deposit, Yachiho Mudflow Deposit, Usonokuchi Gravel Bed, Aikigawa Mudflow Deposit, Yabashirazawa Lava, Kyowabokujo Lava, Hosokojigawa Lava, Shirakabadaira Lava, Ikenotairabokujo Lava)
- Lower limit: Transitional (Oishigawa Scoria), Unconformity (Shiga Welded Tuff)
------ Conformity, ~~~~~~ Unconformity, ~~~--- Local unconformity, '''/,, Interfingered, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown
- Distribution: Kakuma river, Saku city, Nagano pref.; Otake river - Mount Yabashirayama - Mount Kengamine, Sakuho city, Minamisaku county, Nagano pref.
- Tephra: Shindai Volcanic Ash
- Nishiki and Takahashi (2012) Jour. Geol. Soc. Japan, vol.118, no.8, pp.499-515 DOI
- Kawachi (1974) Geology of the Tateshinayama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 114p. (in Japanese with English abstract 5p.)