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Mikasa Formation
It had been included in upper part of Middle Yezo Group.
- Coherent formation
- Yezo forearc basin
- Early Cretaceous, Albian - Late Cretaceous, Turonian (Ammonoids, Inoceramus sp.)
- Contemporaneous heterotopic facies (East): Saku Formation, Lower Hikagenosawa Fomration
- Sedimentary facies: Shallow marine, Terrestrial
- Sedimentary facies: Coastal plain, Incised valley, Inner shelf, Outer shelf, Outer shelf
- Lithofacies: Sandstone, Conglomerate
- Sedimentary structures: Hummocky cross-stratification, Trough cross-stratification, Bio-turbation
------ Conformity, ~~~~~~ Unconformity, ~~~--- Local unconformity, '''/,, Interfingered, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown
- Distribution: Mikasa city - Mnaji, Kurisawa town, Iwamizawa city - Yubari city, Hokkaido
- Distribution: Shikoro creek, Miruto, Kurisawa town, Iwamizawa city, Hokkaido
- Fossils (Ammonoids): Calycoceras (Newboldiceras) orientale, Desmoceras (Pseudouhligella) japonicum, Eucalycoceras pentagonum, Calycoceras (Calycoceras) aff. naviculare, Euomphaloceras septemseriatum, Pseudocalycoceras dentonense, Sciponoceras kossmati, Pachydesmoceras sp. (or Mesopuzosia sp.)
- Fossils: Echinoids, Trigonia (Pterotrigonia sp., Apiotrigonia sp., Yaadia sp.), Oysters, Bivalves (Nanonavis pseudocarinata, Glycymeris hokkaidoensis, Meekia hokkaidoana, Aphrodina pseudoplana, Inoceramus ginterensis, Inoceramus pictus, Inoceramus cf. labiatus, Inoceramus hobetsuensis), Gastropods
- Takashima et al. (2018) Jour. Geol. Soc. Japan, vol.124, no.6, pp.381-398 DOI
- Terabe and Matsuoka (2009) Jour. Geol. Soc. Japan, vol.115, no.3, pp.130-140 DOI
- Ando et al. (2007) Jour. Geol. Soc. Japan, vol.113, Supplement, pp.185-203 DOI