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Sasayama Group (Onoyama, 1931) Hayashi et al., 2017

• Type locality: Sasayama city, Hyogo prefecture
• Coherent formation
• Intermountain basin
• Early Cretaceous, Albian - Late Cretaceous, Cenomanian (105.6 - 96.0 Ma, FT, Ostracods)
• Correlation: Kanmon Group
• Intruded by: Porphyrite dikes, Sills

• Sedimentary facies: Fluvial
• Sedimentary facies (Lower): Channel-fill deposit
• Climate: Sub-humid - Semi-arid
• Lithofacies (Upper): Hornblende andesite Lapilli tuff, Tuff breccia, Tuff, Tuffaceous sandstone, Conglomerate, Mudstone, Sandstone
• Lithofacies (Lower): Sandstone, Mudstone
• Lithofacies (Lower, Minor): Shale, Rhyolite tuff
• Lithofacies (Bottom): Conglomerate
• Sedimentary structures (Lower): Cross stratification, Trace fossils, Slump structure, Convolute lamination

• Thickness: 1,500 m or thicker
• Thickness (Upper): ca. 250 m
• Thickness (Lower): 1,300 m or thicker
• Distribution (East - West): ca. 12 km
• Distribution (South - North): ca. 4 km
• Upper limit: Unconformity (Akus Formation, Lower II Terrace Deposits)
• Lower limit: Unconformity (Ajima Formation, Kaibara Formation, Kamitaki Formation)

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

• Distribution: Hatamiya - Ogami - Seri, Tambasasayama city, Hyogo pref.; Kamitaki - Shimotaki, Tanba city, Hyogo pref.
• Fossils: Sauropods, Mammals, Amphibians, Charophyceae green algae, Chalophyta sp.
• Fossils (Upper, Shellfishes): Nakamuranaia? cf. chingshanensis, Viviparus onogoensis
• Fossils (Upper, Plants): Adiantites sp., Bennettitales? sp., Brachyphyllum japonicum, Cladophlebis sp., Cupressionoxylon sp., Elatocladus sp., Equisetites sp., Frenelopsis sp., Ginkgoites digitata, Otozamites cf. beani, Podozamites cf. lanceolatus
• Fossils (Upper, Estherids): Estherites cf. kyöngsangensis, Estherites cf. kyöngsangensis var. medialis, Estherites cf. nactongensis
• Fossils (Upper, Ostracods): Yanjiestheria sp., Nemestheria aidensis
• Fossils (Lower, Shellfishes): Viviparus cf. keishoensis, Sphaerium coreanicum
• Fossils (Lower, Ostracods): Mongolocypris sp., Eucypris sp.
• Tephra: SSY-2 Tuff

• Hayashi et al. (2017) Jour. Geol. Soc. Japan, vol.123, no.9, pp.747-764 DOI
• Hayashi et al. (2010) Jour. Geol. Soc. Japan, vol.116, no.5, pp.283-286 DOI
• Kurimoto et al. (1993) Geology of the Sasayama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 93p. (in Japanese with English abstract 5p.)
• Imoto et al. (1991) Geology of the Sonobe District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 68p. (in Japanese with English abstract 4p.)