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Toyohama Formation Shibata, 1977

Invalid synonym: Morozaki Formation

• Type locality: Oza, Minamichita city, Chita county, Aichi prefecture
• Coherent formation
• Miocene
• Intruded by: Clastic dikes

• Sedimentary facies: Marine
• Lithofacies (Upper): Sandstone, Interbedded sandstone and mudstone
• Lithofacies (Lower): Interbedded sandstone and mudstone
• Sedimentary structures (Upper): Load cast, Convolute lamination, Slump structures

• Thickness: ca. 700 m
• Upper limit: Bottom of Hajikami Tuffaceous Sandstone
• Upper limit: Conformity (Yamami Formation)
• Lower limit: Bottom of Hasu Tuffaceous Sandstone
• Lower limit: Conformity (Himaka Formation)

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

• Distribution: Toyohama - Cape Hazu - Yamami - Shinyashiki - Oza, Minamichita city, Chita county, Aichi pref.
• Fossils: Crabs (Callianassa sp.)
• Fossils (Fishes): Bathylagus toyohamaensis, Lampadena ozaensis, Myctophidae (Otolith)
• Fossils (Fish scales): Clupeidae, Coryphaenoididae, Myctophidae, Serranidae, Sparidae
• Fossils (Shellfishes): Acesta goliath, Acharax tokunagai, Acila cfr. divaricata, Acilana tokunagai, Bathymalletia chilensis, Bowdenatheca sp., Buccinum mitsuganoensis, Calyptogena sp., Carimineilo takeharai, Chlamys sp., Chlanidota mitsuganoensis, Cyclocardia siogamensis, Ennucula cfr. osawaensis, Euclio balantium, Euspira mitsuganoensis, Fissidentalium cfr. yokoyamai, Laevidentalium sp., Liocyma minuta, Lucinoma acutilineatum, Machaeroplax mitsuganoensis, Macoma? sp., Malletia inermis, Megasureula cfr. osawanoensis, Neilonella isensis, Nipponoscaphander sp., Nuculana pennula, Omniglypta sp., Palliolum (Delectopecten) peckhami, Pandora (Pandorella) cfr. otukai, Periploma mitsuganoense, Phanerolepida cfr. expansilabrum, Pitar sp., Portlandia kakimii, Portlandia cfr. watasei, Poromya sp., Propeamussium tateiwai, Propebela takamiyaensis, Saccella miensis, Tachyrhynchus mitsuganoensis, Tectonatica ichishiana, Thyasira sp., Trominina sp., Trophonopsis cfr. mitsuganoensis, Trophonopsis cfr. soyoe, Turritella ichishiensis, Vaginella depressa, Yoldia sagitoria
• Fossils (Foraminifera): Globigerina euapertura, Globigerina praebulloides pseudociperoensis, Globigerinita dissimilis, Globigerinita stainforthi

• Muramiya et al. (2017) Jour. Geol. Soc. Japan, vol.123, no.11, pp.939-952 DOI
• Kondo and Kimura (1987) Geology of the Morozaki District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 93p. (in Japanese with English abstract 5p.)