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Takafu Formation (Chiji, 1955) Nagamori et al., 2003

Invalid synonym: Takafu Mudstone Member, Horita Formation, Okubo Formation, Okubo Mudstone and Sandstone Member, Hirose Formation

It had been treated as a member of Shigarami Formation.

• Type locality: Dojiri river, Hatsuhiki - Ochiai, Ogawa city, Kamiminochi county, Nagano prefecture
• Coherent formation
• late Miocene - Pliocene (3.6 Ma)
• Contemporaneous heterotopic facies (Middle): Arakurayama Formation, Joshita Member
• Correlation: Tanogashira Formation, Nagaiwa Member
• Intruded by: Basalt, Diorite Porphyry 1, Mujinagoro Body

• Sedimentary facies: Marine
• Lithofacies: Mudstone
• Lithofacies (Upper, Minor): Interbedded sandstone and mudstone, Sandstone, Andesite scoriaceous tuff, Felsic tuff
• Lithofacies (Middle, Minor): Sandstone, Siltstone, Conglomerate, Andesite scoriaceous tuff, Felsic tuff
• Lithofacies (Lower, Minor): Sandstone, Conglomerate
• Sedimentary structures (Middle): Slump structures
• Sedimentary structures (Lower): Gladed bedding, Parallel stratification

• Thickness: 260 - 2,200 m or thicker
• Upper limit: Conformity (Sarumaru Formation, Joshita Member), Interfingered (Arakurayama Formation, Ogikubo Formation), Unconformity (Akada Formation)
• Lower limit: Conformity (Ronji Formation, Arakurayama Formation), Conformity, partly Interfingered (Gonda Formation)

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

• Distribution: Dojiri river, Hatsuhiki - Ochiai, Ogawa city, Kamiminochi county, Nagano pref.; Shimokonabe - Futatsuishi - Okubo, Nagano city, Nagano pref.; Takiya - Kuranami - Hiraide - Yokezawa - Ichiba - Kosaka - Shio - Sewaki, Naniai, Nagano city, Nagano pref.; Yuya - Yamafuse, Shinonoi, Nagano city, Nagano pref.; Sakurai - Higuma, Shinko town, Nagano city, Nagano pref.; Miyamasa - Nakajo - Kusagano, Nakajo, Nagano city, Nagano pref.; Takebusa - Makinoshima, Shinshushinmachi town, Nagano city, Nagano pref.; Nakamaki, Ooka, Nagano city, Nagano pref.; Tatsubashi creek, Hirose - Ageya, Nagano city, Nagano pref.; Higashishige - Takiya, Yamadanaka, Nagano city, Nagano pref.; Susobanaohashi bridge - Tochinoki - Onodaira - Mount Jinbadaira - Funamiya, Nagano city, Nagano pref.; Tsuboyama - Tsumuzawa, Togakushi, Nagano city, Nagano pref.
• Fossils: Echinoids (Linthia nipponica), Trace fossils (Pipe rocks)
• Fossils (Early Shigarami fauna): Anadara amicula, Chlamys sp., Conchocele bisecta, Conchocele nipponica, Corbicula sp., Corbula sp., Dosinia? sp., Glycymeris minochiensis, Lucinoma annulata, Mercenaria chitaniana, Mercenaria sigaramiensis, Mercenaria yokoyamai, Mya (Arenomya) japonica, Ostrea gigas, Panomya simotomensis, Patinopecten yamasakii, Patinopecten yesoensis, Peronidia sp., Turritella saishuensis
• Fossils (Foraminifera): Bulimina pyrula, Cassidulina sp., Cibicides cf. reflugenes, Cyclammina pusilla, Elphidium hanzawai, Epistominella pulchella, Globigerina apertuna, Haplophragmoides cf. evoluta, Haplophragmoides cf. subglobosum, Martinottiella bradyana tarukiensis, Neogloboquadrina dutertrei, Rotalia japonica, Uvigerina akitaensis
• Tephra: OT10

• Seki and Hoyanagi (2015) Jour. Geol. Soc. Japan, vol.121, no.8, pp.279-292, DOI
• Tanabe (2015) Jour. Geol. Soc. Japan, vol.121, no.8, pp.265-278, 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.)
• Nakano et al. (2002) Geology of the Shiroumadake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 105p. (in Japanese with English abstract 5p.)
• Kato et al. (1989) Geology of the Omachi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 111p. (in Japanese with English abstract 7p.)
• 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.)