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Kochigatani Group (Yehara, 1927) Katto et al., 1956

• Type locality (Kasayadani bed, Kochigatani bed): Kochigatani, Sakawa city, Takaoka county, Kochi prefecture
• Type locality (Otogo bed): Otogodani valley, Sakawa city - Ochi city, Takaoka county, Kochi prefecture
• Coherent formation
• Late Triassic, Carnian
• Correlation: Kubotani Formation

• Sedimentary facies: Marine
• Lithofacies (Upper): Sandstone
• Lithofacies (Upper, Minor): Mudstone, Calcareous sandstone
• Lithofacies (Middle): Mudstone
• Lithofacies (Middle, Minor): Felsic tuff
• Lithofacies (Lower): Conglomerate, Sandstone

• Thickness (Upper): 450 m or thicker
• Thickness (Middle): 200 m or thicker
• Thickness (Lower): 180 m or thicker
• Upper limit: Unconformity (Sakashu Group)

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

• Distribution: Kochigatani - Mount Kaisekiyama, Sakawa city, Takaoka county, Kochi pref.; Otogodani valley, Sakawa city - Ochi city, Takaoka county, Kochi pref.; Kamimotomiya town, Kochi city, Kochi pref.; Tatsuishi, Hidaka city, Takaoka county, Kochi pref.; Sakashu, Naga city, Naga county, Tokushima pref.
• Fossils: Crinoids (Balanocrinus sp., Isocrinus? sp.), Plants (Equisetites? sp., Podozamites sp.), Foraminifera (Spirillina orbicula), Radiolarians (Copiellintra sp.), Bryozoans (Pseudobatostomella kobayashii)
• Fossils (Ammonoids): Arcestes? sp., Cyrtopleurites sakawanus, Paratrachyceras cf. hofmanni, Proarcestes aff. bicarinatus
• Fossils (Shellfishes): Cassianella? dubia, Chlamys mojsisovicsi, Cultellus? ellipsoidalis, Cuspidaria? sp., Eopecten? infrequensis, Eopecten? sumeriensis, Eumorphotis aff. spitzbergensis, Halobia alta, Halobia aotii, Halobia kashiwaiensis, Halobia kawadai, Halobia longissima, Halobia molukkana, Halobia multilineata, Halobia obsoleta, Halobia sedaka, Megalodon sp., Minetrigonia katayamai, Modiolus paranaiformis, Monotis mabara, Monotis ochotica densistriata, Monotis ochotica ochotica, Monotis zabaikalica, Mytilus (Falcimytilus) nasai, Mytilus (Falcimytilus?) tenuiformis, Neoschizodus (Neoschizodus) dieneri, Neoschizodus (Neoschizodus) nakajimensis, Neoschizadus (Neoschizodus) usugataniensis, Neoschizodus (Okunominetania) okunominetaniensis, Nucula? iwayai, Otapiria dubia, Oxytoma? dieneri, Oxytoma kashiwaiensis, Oxytoma mojsisovicsi, Oxytoma sujimabara, Palaeoneilo tenelliformis, Palaeopharus oblongatus, Parallelodon? infrequens, Plagiostoma kuromagariensis, Pleuromya forsbergi nipponica, Pseudolimea naumanni, Sakawanella triadica, Schafhaeutlia mellingi japonica, Tosapecten pseudohiemalis, Tosapecten suzukii, Triaphorus trapezoidalis, Trigonucula sakawana, Unionites carinatus, Unionites kochigataniensis
• Fossils (Brachiopods): Punctospirifer triadicus, Punctospirifer triadicus kashiwaiensis, Rhynchonella kochigataniensis, Rhynchonella nakajimensis, Sakawairhynchia katayamai, Sakawairhynchia tokomboensis, Spiriferinoides nasai, Spiriferinoides sakawanus, Spiriferinoides yeharai, Terebratula sp.
• Fossils (Trace fossils): aff. Anchonicus isp., Planolites isp.

• Wakita et al. (2007) Geology of the Ino District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 140p. (in Japanese with English abstract 4p.)
• Ishida (2007) Jour. Geol. Soc. Japan, vol.113, no.3, pp.83-94 DOI