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Nakazawa Formation Ozawa et al., 1984

• Type locality: Shimonakazawa - Inubuse, Noshiro city, Akita prefecture
• Coherent formation
• Pleistocene

• Sedimentary facies (Northeast, Upper): Mudflat, Lacustrine
• Sedimentary facies (Northeast, Lower): Marine
• Sedimentary facies (Southwest): Shallow marine
• Water temperature: Cold ocean current
• Lithofacies: Sandstone
• Lithofacies (Lower, Minor): Acidic tuff, Sandy tuff, Siltstone, Lignite, Conglomerate

• Thickness: 40 - 420 m
• Upper limit: Unconformity (High I Terrace Deposit, Katanishi Formation)
• Lower limit (Southwest): Bottom of the soft sandstone bed overlying hard sandstone
• Lower limit (Northeast): Unconformity (Tentokuji Formation, Sasaoka Formation)
• Lower limit (Southwest): Conformity (Sasaoka Formation)

• Distribution: Shimonakazawa - Inubuse, Noshiro city, Akita Akita pref.; Shinden - Masayama creek, Futatsui town, Noshiro city, Akita pref.; Nakakumazawa, Mitane city, Yamamoto county, Akita pref.
• Fossils: Plant fragments, Foraminifera
• Fossils (Shellfishes): Acila insignis, Anadara amicula, Anisocorbula venusta, Antiplanes contraria, Arca boucardi, Astarte borealis, Barbatia stearnsii, Bathyarca kyurokuzimana, Boreotrophon beringi, Brachytoma japonica, Carditella toneana, Chlamys cosibensis, Cryptonatica janthostomoides, Dentalium octangulatum, Eunaticina papilla, Euspira pila, Fabulina miyatensis, Fabulina nitidula, Glycymeris pilsbryi, Glycymeris yessoensis, Leptothyra sangarensis, Limatula japonica, Limopsis tokaiensis, Mercenaria stimpsoni, Mizuhopecten tokyoensis, Mizuhopecten yessoensis, Mizuhopecten yessoensis yokoyamae, Monia radiata, Myadora japonica, Mytilus sp., Neverita didyma, Notoacmea concinna, Notoacmea schrenkii, Olivella fabula, Ophiodermella miyatensis, Ophiodermella pseudopannus, Pecten albicans, Phalium strigosum, Placamen tiara, Plicifusus plicatus, Porterius dalli, Porterius obliquatus, Propebela yokoyamai, Puncturella fastigata, Puncturella nobilis, Pyrene burchardi, Saccella sp., Solamen diaphana, Succella sp., Tritia acutidentata, Tritia luteola, Tritonalia adunca, Turritella fortilirata, Turritella nomurai, Venericardia ferruginea, Yoldia johanni
• Fossils (Foraminifera): Cassidulina subglobosa, Cibicides lobatulus, Cibicides reflugenes, Cibicides pseudoungerianus, Discopluvinulina bradyi, Discorbis opercularis, Elphidium advenum, Elphidium cf. fabum, Elphidium fax barbarensis, Elphidium hughesi foraminosum, Eponides frigidus, Eponides karsteni, Gaudryna quadranglaris, Guttulina spp., Planulina wuellerstorfi, Polistomellina discorbinoides, Psudononion japonica, Quinqueloculina spp., Reussella haizumensis, Rotalia beccari, Rotalia nipponica, Rotalia papillosa, Sigmoidella kagaensis

• Ozawa et al. (1985) Geology of the Ugo-Hamada District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 57p. (in Japanese with English abstract 4p.)
• Ozawa et al. (1985) Geology of the Moritake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 69p. (in Japanese with English abstract 5p.)
• Ozawa et al. (1984) Geology of the Noshiro District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 91p. (in Japanese with English abstract 9p.)