Inagodake Pyroclastic Flow Deposit

Type locality: northern part of Mount Yatsugatake, Nagano prefecture
Volcanic rocks
Pleistocene - Holocene

Lithofacies: Hornblende andesite pyroclastic flow deposit

Thickness: 20 m
Running distance: ca. 40 km
Upper limit: Shirakomaike-toho Lavas, , Unconformity (Yokoyamakyo Lava)
Lower limit: Unconformity (Kagikake Formation, Usonokuchi Gravel Bed, Tomyodaira Pyroclastic Rocks, Kaize Formation)

Northern Yatsugatake volcanoes
[ Upper ]
+__+__+__+__+_
Shirakomaike-toho Lavas
~~~~~~~~~~~~~~
Maruyama Lava
~~~~~~~~~~~~~~
Shimagareyama-toho Lava
~~~~~~~~~~~~~~
Chausuyama Lava
~~~~~~~~~~~~~~
Amaike-toho Lava
~~~~~~~~~~~~~~
Shirakabadaira Lava
~~~~~~~~~~~~~~
Ikenotaira-bokujo Lavas
~~~~~~~~~~~~~~
Yokodake Basal Lava
~~~~~~~~~~~~~~
Arakuragawa Lava
~~~~~~~~~~~~~~
Yokoyakyo Lavas
~~~~~~~~~~~~~~
Inagodake Lavas
~~~~~~~~~~~~~~
Inagodake Pyroclastic Flow Deposit
~~~~~~~~~~~~~~
Shirakoma-rindo Lava
~~~~~~~~~~~~~~
[ Lower ]

Yatsugatake volcanoes (North of Natsuzawa pass)
[ Upper ]
+__+__+__+__+_
Northern Yatsugatake volcanoes
~~~~~~~~~~~~~~
[ Lower ]

------ Conformity, ~~~~~~ Unconformity, ~~~--- Local unconformity, '''/,, Interfingered, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown

Distribution: Lake Matsubara - Lake Yanaike - Goko - Honma river - Komihara, Komi city, Minamisaku county, Nagano pref.; Umijiri, Minamimaki city, Minamisaku county, Nagano pref.; Usonokuchi - Kaise, Sakuho city, Minamisaku county, Nagano pref.

Nishiki et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.5, pp.193-211 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.)