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Tomobe Formation Sakamoto and Unozawa, 1979

• Type locality: Tomobe hills, Tomobe, Kasama city, Ibaraki prefecture
• Coherent formation
• middle Pleistocene
• Correlation: Jizodo Formation

• Sedimentary facies: Marine
• Sedimentary facies: Delta filling inner bay
• Lithofacies (Upper): Sands, Silty sands
• Lithofacies (Middle): Sands
• Lithofacies (Lower): Sands, Silt
• Lithofacies (Lower, Minor): Conglomerate
• Sedimentary structures: Parallel stratification
• Sedimentary structures (Middle): Cross stratification
• Sedimentary structures (Minor): Loess dolls (Rootlets)
• Paleocurrent: Northwest to Southeast

• Thickness: ca. 40 - 60 m
• Upper limit: Unconformity (Namegata Member, Middle II Terrace Deposit)
• Lower limit: Unconformity (Granitoids, Metamorphic rocks)

• Distribution: Tomobe, Kasama city, Ibaraki pref.; Uchihara town, Mito city, Ibaraki pref.
• Fossils: Corals, family Caryophylliidae
• Fossils (Shellfishes): Angulus cf. vestalioides, Barbatia sp., Callithaca adamsii, Calyptraea cf. yokoyamai, Chlamys (Azumapecten) farreri farreri, Chlorostoma cf. argyrostoma, Clinocardium (Keenocardium) californiense, Clinocardium nuttallii, Cryptomya cf. busoensis, Cryptonatica janthostomoides, Cycladicama cumingii, Cyclocardia cf. ferruginea, Dentalium sp., Fulvia mutica, Fuscocardium braunsi, Inquisitor sp., Lucinoma concentricum, Macoma tokyoensis, Meretrix sp., Mizuhopecten tokyoensis, Moerella cf. iridescens, Mya (Arenomya) arenaria oonogai, Pandorella sp., Panopea japonica, Pecten (Notovola) albicans, Phacosoma nipponicum, Pitar (PItarina) sp., Raetellops pulchella, Reticunassa cf. japonica, Saxidomus purpuratus, Scapharca broughtonii, Scapharca subcrenata, Siphonalia sp., Solen (Ensisolen) krusensterni, Spisula (Mactromeris) polynympha, Zeuxis sp.
• Fossils: Pipe rocks

• Miyazaki et al. (1996) Geology of the Makabe District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 103p. (in Japanese with English abstract 4p.)
• Sakamoto et al. (1981) Geology of the Ishioka District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 50p. (in Japanese with English abstract 3p.)