Ohno Formation

Invalid synonym: Shimoda Formation

Coherent formation
early Miocene (20 - 17 Ma, Radiolarians)

Sedimentary facies: Marine
Sedimentary facies: Inner bay (Shellfishes)
Depth of water: 20 m or shallower (Upper part of upper sublittoral zone, Shellfishes)
Lithofacies: Mudstone
Lithofacies (Minor): Sandstone, Interbedded sandstone and mudstone, Felsic tuff, Tuffaceous mudstone

Upper limit: Conformity (Kadoya Formation)
Lower limit: Conformity (Kawakado Formation)

Hokusetsu Subgroup
[ Upper ]
~~~~~~~~~~~~~~
Kadoya Formation
--------------
Ohno Formation
--------------
Kawakado Formation
--------------
Taguchi Formation
~~~~~~~~~~~~~~
[ Lower ]

Shitara Group
[ Upper ]
?--?--?--?--?-
Nansetsu Subgroup (Shitara Volcanic Rocks)
~~~~~~~~~~~~~~
Hokusetsu Subgroup
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Taguchi, Shitara city, Kitashitara county, Aichi pref.; Ebi - Kuroze, Shinjo city, Aichi pref.; Midono river, Toei city, Kitashitara county, Aichi pref.
Fossils (Shellfishes): Lucinoma acutilineatum, Macoma izurensis, Macoma optiva, Chlamys cf. iwamurensis, Fissidentalium sp., Turritella ichishiensis
Fossils (Radiolarians): Cyrtocapsella tetrapera, Cenosphaera coronata, Cenosphaera cf. coronataformis
Fossils (Trace): Phycosiphon incertum

Hoshi and Ogawa (2012) Jour. Geol. Soc. Japan, vol.118, no.11, pp.748-761 DOI
Hoshi and Saida (2009) Jour. Geol. Soc. Japan, vol.115, no.5, pp.193-205 DOI