Dedana Formation

Dedana Formation (Otsuka, 1932) Takano, 1994

Type locality: Yomiuri Golf Club, Yanokuchi, Inagi city, Tokyo
Coherent formation
Fore-arc basin sediments (Kazusa trough)
early Pleistocene (1.5 - 1.3 Ma)
Interfingered: Ozenji Formation
Interfingered (Lower): Kakio Formation

Lithofacies: Sands
Lithofacies (Middle): Mud
Lithofacies (Middle, Minor): Wood fragments
Lithofacies (Minor): Gravels
Sedimentary structures: Cross stratification, Parallel stratification

Thickness: 15 - 125 m
Thickness (Middle): 5 m or thicker
Thickness (Lower): 3 - 10 m
Upper limit: Conformity (Ikuta Formation), Unconformity (Gotentoge Terrace Deposit)
Lower limit: Top of the horizon intercalating many conglomerate beds
Lower limit: Conformity (Inagi Formation)

Kazusa Group (western Tama hills)
[ Upper ]
~~~~~~~~~~~~~~
Dedana Formation
--------------
Inagi Formation
--------------
Renkoji Formation
~~~~~~~~~~~~~~
Oyamada Formation
--------------
Hirayama Formation
--------------
Oyabe Formation
--------------
Terada Formation
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Yanokuchi - Wakabadai - Koyodai - Sakahama, Inagi city, Tokyo; Suge, Tama ward, Kawasaki city, Kanagawa pref.; Hosoyama - Chiyogaoka - Takaishi - Yurigaoka, Asao ward, Kawasaki city, Kanagawa pref.
Tephra: Hosoyama Tuff, MT

Suzuki et al. (2016) Jour. Geol. Soc. Japan, vol.122, no.7, pp.343-356, DOI
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.)
Suzuki and Murata (2011) Jour. Geol. Soc. Japan, vol.117, no.7, pp.379-397 DOI
Oka et al. (1984) Geology of the Tokyo-Seinambu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 148p. (in Japanese with English abstract 7p.)