[ Top ] [ Japanese ]

Shiozawa Formation

• Type locality: Shiozawa, Yamakita city, Ashigarakami county, Kanagawa prefecture
• Coherent formation
• Trough-fill sediments between the plate of Honshu side and the Izu block,, an island arc - island arc collision zone

• Sedimentary facies: Marine, Fluvial
• Sedimentary facies (Upper): Delta
• Sedimentary facies (Middle): Fan delta
• Sedimentary facies (Lower): Inner bay, Tidal flat
• Lithofacies (Upper, Main): Conglomerate with gravels of plutonic rocks
• Lithofacies (Upper, Minor): Sandstone
• Lithofacies (Middle-Lower, North, Main): Conglomerate with gravels of plutonic rocks
• Lithofacies (Middle-Lower, North, Minor): Sandstone
• Lithofacies (Middle-Lower, South): Sandstone-dominant interbedded sandstone and conglomerate

• Thickness (Upper): 700 m
• Thickness (Middle): 1,300 m
• Thickness (Lower): 500 m
• Upper limit: Conformity (Ikudo Formation, Old Somma Deposits of Hakone volcano)
• Upper limit: Unconformity (Suruga Gravels Formation)

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

• Distribution: Kawachi river - Jizodo, Yamakita city, Ashigarakami county, Kanagawa pref.
• Distribution (Upper): Oyama, Oyama city, Sunto county, Shizuoka pref.; Shiozawa, Yamakita city, Ashigarakami county, Kanagawa pref.
• Distribution (Lower): Ayuzawa river, Morobuchi, Yamakita city, Ashigarakami county, Kanagawa pref.
• Fossils (Lower): Parastegodon sp.�iMolar), Deers (Carvidae gen et sp., indet), Picea cf. koribai, Metasequoia sp. (Cones), Trunks
• Fossils (Lower, Bivalves): Oysters (Crassostrea gigas), Trapezium liratum, Meretrix lusoria, Tapes philippinarum, Macoma incongrua, Mya arenaria oonogai
• Fossls (Lower, Gastropods): Chiazacmea pygmaea lampanicola, Littorina brevicula, Reticunassa festiva

• Ishikawa et al. (2016) Jour. Geol. Soc. Japan, vol.122, no.7, pp.291-304, DOI
• Odawara et al. (2011) Jour. Geol. Soc. Japan, vol.117, Supplement, pp.135-152 DOI