Hosoya Tuffaceous Silt Member

Coherent formation
Pliocene - early Pleistocene

Sedimentary facies: Marine
Sedimentary facies: Forearc basin (Sagara-Kakegawa Basin) deposit
Lithofacies: Tuffaceous silt

Thickness: ca. 35 - 80 m

Upper Kakegawa Formation
[ Upper ]
~~~~~~~~~~~~~~
Aburayama Sand Member
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Hijikata Mud Member
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Nango Sand Mud Alternation Member
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Hosoya Tuffaceous Silt Member
--------------
[ Lower ]

Kakegawa Group (Kakegawa, Shizuoka pref.)
[ Upper ]
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Soga Formation
~~~~~~~~~~~~~~
Upper Kakegawa Formation
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Lower Kakegawa Formation
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[ Lower ]

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

Distribution: Kakegawa city, Shizuoka pref.; Ugari - Yamanashi, Fukuroi city, Shizuoka pref.; Sonoda - Iida, Mori city, Shuchi county, Shizuoka pref.
Fossils: Foraminifera (Baggina totomiensis), Plants
Fossils (Shellfishes): Acila mirabilis, Anomia lischkei, Bittium misellissimum, Cancellaria kobayashii, Chlamys (Aequipecten) vesiculosus, Chlathrodrillia totomiensis, Chlathrodrillia jeffreysii, Crassatellites nanus, Dentalium totomiensis, Glycymeris rotunda, Nassaria magnifica, Neverita reiniana, Paphia schnelliana, Paradrillia dainichiensis, Pecten tokyoensis, Siphonalia declivis, Siphonalia modificata, Siphonalia tonohamaensis totomiensis, Teleutodrillia nakamurai, Turricula subdeclivis, Turris totomiensis, Venus (Ventricola) casinaeformis, Vexillum nakamurai ugaliensis

Makiyama and Sakamoto (1957) Mitsuke & Kakezuka, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 43p. (in Japanese with English abstract 7p.)