Nakatsu Group

Invalid synonym: Nakatsu Formation

Type locality: Sagami river, Kosawa, Aikawa city, Aiko county, Kanagawa prefecture
Coherent formation
late Pliocene - Pleistocene

Sedimentary facies: Shallow marine, Deep sea
Water temperature: Warm ocean current

Thickness: 470 - 670 m or thicker
Upper limit: Unconformity (Mukaihara Formation, Zama Hills Terrace Deposit, Sagamihara Terrace Deposit, Tanahara Terrace Deposit, Minahara Terrace Deposit)
Lower limit: Unconformity (Kobotoke Group)

Nakatsu Group
[ Upper ]
~~~~~~~~~~~~~~
Shioda Formation
--------------
Otsuka Formation
--------------
Shimizu Formation
--------------
Kanzawa Formation
--------------
Kosawa Formation
~~~~~~~~~~~~~~
[ Lower ]

Kazusa Group (Sagami river)
[ Upper ]
~~~~~~~~~~~~~~
Nakatsu Group
~~~~~~~~~~~~~~
[ Lower ]

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

Fossils (Upper, Shellfishes): 82 species

Fossils (Lower, Shellfishes): 140 species

Distribution: Kosawa - Sakamoto, Aikawa city, Aiko county, Kanagawa pref.; Saido - Ichijima, Atsugi city, Kanagawa pref.

Ueki et al. (2013) Geology of the Hachioji District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 137p. (in Japanese with English abstract 6p.)
Tamura et al. (2010) Jour. Geol. Soc. Japan, vol.116, no.7, pp.360-373 DOI
Oka et al. (1979) Geology of the Fujisawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 111p. (in Japanese with English abstract 5p.)