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Minamigo Formation Toyono Collaborative Research Group, 1974

Invalid synonym: Asahiyama Formation

• Type locality: Tagosawa, Minamigo, Toyono, Nagano city, Nagano prefecture
• Coherent formation
• Late Pleistocene

• Sedimentary facies: Lacustrine
• Climate: Cool similar to subalpine (Pollen)
• Lithofacies: Gravels
• Lithofacies (Minor): Tuffaceous sands, Silt, Clay, Peat
• Sedimentary structures: Cross stratification

• Thickness: ca. 40 m
• Upper limit: Unconformity (Alluvial fan deposit, Colluvium deposit)
• Lower limit: Unconformity (Toyono Formation, Susobana Formation, Nishigawara Formation)

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

• Distribution: Minamigo - Kose, Toyono, Nagano city, Nagano pref.; Tanaka - Asakawa-Nishijo - Dokyo river - Mount Shiroyama - Hirashiba - Kanayamazawa - Nakaoyama hot spring, Nagano city, Nagano pref.; Kusama - Lake Hamatsugaike, Nakano city, Nagano pref.
• Fossils: Elephants (Palaeoloxodon naumanni)
• Fossils (Plants): Abies sp., Alnus sp., Aquifoliaceae, Castanea sp., Compositae, Epithemia sp., Ericaceae, Fagus sp., Inaperturopoll sp., Juglans sieboldiana, Melosira sp., Navicula sp., Palmae, Pinus sp., Pterocarya sp., Quercus sp., Synedra sp.
• Fossils (Diatoms): Epithemia sp., Melosira sp., Navicula sp., Synedra sp.
• Fossils (Pollen): Abies sp., Alnus sp., Aquifoliaceae, Castanea sp., Compositae, Ericaceae, Fagus sp., Inaperturopoll (Glyptostrobus sp. and others), Juglans sp., Palmae, Pinus sp., Pterocarya sp., Quercus sp.

• Sugito et al. (2015) Jour. Geol. Soc. Japan, vol.121, no.7, pp.217-232, DOI
• Nagamori et al. (2003) Geology of the Togakushi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 109p. (in Japanese with English abstract 3p.)
• Akahane et al. (1992) Geology of the Nakano District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 106p. (in Japanese with English abstract 4p.)
• Kato and Akahane (1986) Geology of the Nagano District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 120p. (in Japanese with English abstract 5p.)