Shijuhassegawa Formation

[ Top ] [ Japanese ]

Shijuhassegawa Formation

Volcanic rocks
Oceanic arc of Paleo-Izu-Bonin arc
Mountain flank deposits of submarine volcanos and volcanic islands on Tanzawa mass
Early Miocene (17.0 - 16.0 Ma)

Sedimentary facies: Marine
Metamorphic facies: Prehnite-Pumpellyite
Lithofacies: Subaqueous volcaniclastics, Subaqueous lavas
Lithofacies: Basaltic lavas, Hyaloclastite, Epiclastic turbidite

Thickness: 250 - 1,100 m
Upper limit: Conformity
Lower limit: Conformity

Togatake Subgroup
[ Upper ]
--------------
Shijuhassegawa Formation
--------------
Yadorigizawa Formation
--------------
[ Lower ]

Tanzawa Group
[ Upper ]
~~~~~~~-------
Susugaya Subgroup
--------------
Oyama Subgroup
--------------
Togatake Subgroup
--------------
[ Lower ]

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

Distribution: Tanzawa mountains, Kanagawa pref.

Ishikawa et al. (2016) Jour. Geol. Soc. Japan, vol.122, no.7, pp.291-304, 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.)
Matsubara and Amano (2010) Jour. Geol. Soc. Japan, vol.116, no.3, pp.134-150 DOI