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Mita Formation (Nakaseko, 1954) Hayakawa and Takemura, 1987

• Type locality: Mita, Yatsuo village, Toyama city, Toyama prefecture
• Coherent formation
• late Pliocene - early Pleistocene (5.2 - 2.2 Ma, Shellfishes)

• Sedimentary facies: Marine, Fluvial
• Sedimentary facies: Lower shoreface
• Sedimentary facies (Top): Strong influence of warm current
• Sedimentary facies (Upper): Open bay
• Sedimentary facies (Lower): Offshore, Warm current
• Climate (Upper): Temperate
• Climate (Lower): Cold temperate
• Depth of water (Upper): Upper sublittoral zone
• Depth of water (Upper, North): Lower sublittoral zone
• Depth of water (Lower): Upper sublittoral zone
• Lithofacies: Sandstone (without plant frangments)
• Lithofacies (Minor): Conglomerate, Tuff
• Sedimentary structures (Upper): Wave-formed ripples, Swaley cross-stratification

• Thickness: ca. 320 m
• Upper limit: Unconformity (Kurehayama Gravel Bed)
• Lower limit: Bottom of conglomerate bed ca. 10 m lower than OT3 Tephra (Ravinement erosion surface or Sequence boundary).
• Lower limit: Unconformity (Otogawa Formation)

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

• Distribution: Mita, Yatsuo town, Toyama city, Toyama pref.; Yamada river, Chisato - Yoshizumi, Fuchu town, Toyama city, Toyama pref.; Akae river, Renge, Fuchu town - Hirabayashi, Yatsuo town, Toyama city, Toyama pref.
• Fossils: Ostracodes, Planktonic foraminifera, Nannofossils
• Fossils (Omma-Manganji fauna): Acila divaricata, Acila insignis, Yoldia notabilis, Portlandia sp., Saccella confusa, Saccella sematensis, Modiolus difficilis, Mitylidae gen. et sp. indet., Solamen spectabilis, Megacrenella columbiana, Musculus cupreus, Arca boucardi, Barbatia sp., Anadara amicula, Anadara cf. tatunokutiensis, Anadara ommaensis, Striaraca symmetrica, Limopsis cumingii, Limopsis oblonga, Glycymeirs yessoensis, Glycymeirs nipponica, Limaria hirasei, Limaria hakodatensis, Limatula kurodai, Ostrea sp., Chlamys cosibensis, Chlamys farreri nipponensis, Chlamys ingeniosa tanakai, Chlamys cf. jousseaumei, Chlamys tanassevitschi, Chlamys aff. senatoria, Swiftopecten swiftii, Mizuhopecten yamasakii, Mizuhopecten tokyoensis, Mizuhopecten tryblium, Mizuhopecten yokoyamae, Mizuhopecten yessoensis, Yabepecten tokunagai, Anomia chinensis, Monia macroschisma, Chama sp., Wallucina? sp., Divaricella soyoae, Lucinoma annulata, Lucinidae gen. et sp. indet., Cycladicama? sp., Felaniella usta, Felaniella ohtai, Cardita leana, Megacardita ferruginosa, Cyclocardia ferruginea, Miodontiscus prolongatus nakamurai, Astarte hakodatensis, Tridonta borealis, Clinocardium californiense, Clinocardium fastosum, Clinocardium ciliatum, Dinocardium anugustum, Serripes groenlandicus, Profulvia kurodai, Spisula grayana, Siliqua alta, Raeta? sp., Solen krusensterni, Megangulus zyonoensis, Cadella lubrica, Fabulina nitidula, Macoma calcarea, Macoma nipponica, Macoma lama meridionalis, Macoma optiva, Macoma middendorff, Macoma ingongrua, Macoma sectior, Leptomya cuspidariaeformis, Gari sp., Gobraeus kazusensis, Nuttallia cf. commoda, Placamen tiara, Veremolpa micra, Securella stimpsoni, Securella chitaniana, Protothaca tateiwai, Circe scripta, Callista chinensis, Ezocallisata brevisiphonata, Pseudamiantis tauyensis, kaneharaia ausiensis, Phacosoma tomikawensis, Liocyma? sp., Clementia vatheleti, Clementia papyracea, Mya cuneiformis, Cryptomya busoensis, Anisocorbula venusta, Varicobula? sp., Panomya simotomensis, Panopea japonica, Thracia kakumana, Thracia kamayasikiensis, Entodesma naviculoides, Pandora wardiana, Pandora pulchella, Myadora fluctuosa, Myadora japonica, Cuspidaria sp., Dentalium octangulatum, Fissidentalium yokoyamai, Lottia? sp., Acmaea pallida, Notoacmaea sp., Emarginula sp., Tugurium exutum, Tugali sp., Puncturella nobilis, Diodora? sp., Homalopoma amussitatum, Pomaulax cf. omorii, Turcica cf. coreensis, Cantharidus sp., Minolia aff. punctata, Umbonium akitanum, Trochidae gen. et sp. indet., Rhinoclavis sp., Bittium sp., Turritella nipponica, Turritella saishuensis saishuensis, Turritella saishuensis motidukii, Turritella fortililata, Sabia? sp., Crepidula grandis, Serpulorbis sp., Calyptraeidae gen. et sp. indet., Euspira pila, Glossaulax didyma didyma, Mammilla sp., Cryptonatica janthostoma, Naticidae gen. et sp. indet., Cassidae gen. et sp. indet., Fusitriton oregonensis, Boreotrophon candelabrum, Pteropurpura? sp., Ocinebrellus sp., Ancistrolepis grammatus, Mohnia yanamii, Neptunea modesta, Neptunea eulimata, Neptunea arthritica, Siphonalia fusoides, Siphonalia modificata, Cantharus sp., Babylonia elata, Buccinum rhodium, Lirabuccinum cf. japonicum, Reticunassa acutidentata, Fusinus tuberosus, Fulgoraia aff. elongata, Olivella sp., Cancellaria? sp., Admete? sp., Aforia? sp., Antiplanes contraria, Rectiplanes? sp., Paradrillia sp., Inquisitor sp., Ophiodermella sp., Suavodrillia declivis, Oenopota sp., Propebela? sp., Odostomia sp., Syrnola sp., Turbonilla sp., Leucotina gigantea, Haloa? sp., Acteon? sp.
• Fossils (Calcareous nannnofossils, 3.7 - 2.8 Ma): Reticulofenestra spp., Coccolithus pelagicus, Gephyrocapsa sp.
• Fossils (Trace fossils): Ophiomorpha isp., Rosselia isp.
• Tephra: OT3, OT4 (= Kosugaya Tephra, 4 Ma), OT5, MT1, Shimose Tuff, MT2, Taniguchi Tuff, Rengeji 1 Tuff, Rengeji 2 Tuff

• Nakajima et al. (2019) Jour. Geol. Soc. Japan, vol.125, no.7, pp.483-516 DOI
• Goto et al. (2014) Jour. Geol. Soc. Japan, vol.120, no.2, pp.71-86 DOI
• Tamura et al. (2010) Jour. Geol. Soc. Japan, vol.116, Supplement, pp.1-20 DOI
• Amano et al. (2008) Jour. Geol. Soc. Japan, vol.114, no.10, pp.516-531 DOI