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

Invalid synonym: Mita Sandstone Member

• Type locality: Mita, Yatsuo village, Toyama city, Toyama prefecture
• Coherent formation
• late Pliocene - early Pleistocene (5.2 - 2.2 Ma, Shellfishes)
• Correlation (Upper): Chokeiji Sand Member
• Correlation (Lower): Anyobo Sandstone and Mudstone Alternation Member

• 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 (Hirabayashi Sandstone Member)

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

• Distribution: Mita, Yatsuo town, Toyama city, Toyama pref.; Chisato - Yoshizumi - Yamadagawa river - Hirabayashi - Renge - Akaegawa river - Hirabayashi, Yatsuo town, Toyama city, Toyama pref.
• Fossils: Ostracodes, Planktonic foraminifera, Nannofossils
• Fossils (Omma-Manganji fauna): Acila divaricata, Acila insignis, Acmaea pallida, Acteon? sp. Admete? sp., Aforia? sp., Anadara amicula, Anadara ommaensis, Anadara cf. tatunokutiensis, Ancistrolepis grammatus, Anisocorbula venusta, Anomia chinensis, Antiplanes contraria, Arca boucardi, Astarte hakodatensis, Babylonia elata, Barbatia sp., Bittium sp., Boreotrophon candelabrum, Buccinum rhodium, Cadella lubrica, Callista chinensis, Calyptraeidae gen. et sp. indet, Cancellaria? sp., Cantharidus sp., Cantharus sp., Cardita leana, Cassidae gen. et sp. indet, Chama sp., Chlamys cosibensis, Chlamys farreri nipponensis, Chlamys ingeniosa tanakai, Chlamys cf. jousseaumei, Chlamys aff. senatoria, Chlamys tanassevitschi, Circe scripta, Clementia papyracea, Clementia vatheleti, Clinocardium californiense, Clinocardium ciliatum, Clinocardium fastosum, Crepidula grandis, Cryptomya busoensis, Cryptonatica janthostoma, Cuspidaria sp., Cycladicama? sp., Cyclocardia ferruginea, Dentalium octangulatum, Dinocardium anugustum, Diodora? sp., Divaricella soyoae, Emarginula sp., Entodesma naviculoides, Euspira pila, Ezocallisata brevisiphonata, Fabulina nitidula, Felaniella ohtai, Felaniella usta, Fissidentalium yokoyamai, Fulgoraia aff. elongata, Fusinus tuberosus, Fusitriton oregonensis, Gari sp., Glossaulax didyma didyma, Glycymeirs nipponica, Glycymeirs yessoensis, Gobraeus kazusensis, Haloa? sp., Homalopoma amussitatum, Inquisitor sp., Kaneharaia ausiensis, Leptomya cuspidariaeformis, Leucotina gigantea, Limaria hakodatensis, Limaria hirasei, Limatula kurodai, Limopsis cumingii, Limopsis oblonga, Liocyma? sp., Lirabuccinum cf. japonicum, Lottia? sp., Lucinidae gen. et sp. indet, Lucinoma annulata, Macoma calcarea, Macoma ingongrua, Macoma lama meridionalis, Macoma middendorff, Macoma nipponica, Macoma optiva, Macoma sectior, Mammilla sp., Megacrenella columbiana, Megangulus zyonoensis, Megacardita ferruginosa, Minolia aff. punctata, Miodontiscus prolongatus nakamurai, Mitylidae gen. et sp. indet, Mizuhopecten tokyoensis, Mizuhopecten tryblium, Mizuhopecten yamasakii, Mizuhopecten yessoensis, Mizuhopecten yokoyamae, Modiolus difficilis, Mohnia yanamii, Monia macroschisma, Musculus cupreus, Mya cuneiformis, Myadora fluctuosa, Myadora japonica, Naticidae gen. et sp. indet, Neptunea arthritica, Neptunea eulimata, Neptunea modesta, Notoacmaea sp., Nuttallia cf. commoda, Ocinebrellus sp., Odostomia sp., Oenopota sp., Olivella sp., Ophiodermella sp., Ostrea sp., Pandora pulchella, Pandora wardiana, Panomya simotomensis, Panopea japonica, Paradrillia sp., Patinopecten kurosawaensis, Phacosoma tomikawensis, Placamen tiara, Pomaulax cf. omorii, Portlandia sp., Profulvia kurodai, Propebela? sp., Protothaca tateiwai, Puncturella nobilis, Raeta? sp., Pseudamiantis tauyensis, Pteropurpura? sp., Reticunassa acutidentata, Saccella confusa, Saccella sematensis, Securella chitaniana, Securella stimpsoni, Rectiplanes? sp., Rhinoclavis sp., Sabia? sp., Serpulorbis sp., Serripes groenlandicus, Siliqua alta, Siphonalia fusoides, Siphonalia modificata, Solamen spectabilis, Solen krusensterni, Spisula grayana, Striaraca symmetrica, Suavodrillia declivis, Swiftopecten swiftii, Syrnola sp., Tillina? sp., Thracia kakumana, Thracia kamayasikiensis, Tridonta borealis, Trochidae gen. et sp. indet, Tugali sp., Tugurium exutum, Turbonilla sp., Turcica cf. coreensis, Turritella fortililata, Turritella nipponica, Turritella saishuensis motidukii, Turritella saishuensis saishuensis, Umbonium akitanum, Varicobula? sp., Venericardia ferruginea, Veremolpa micra, Volsella sp., Wallucina? sp., Yabepecten tokunagai, Yoldia notabilis
• 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
• Sakamoto and Nozawa (1960) Yatsuo, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 69p. (in Japanese with English abstract 8p.)