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Volcaniclastic deposits

• Type locality: Toshima city, Tokyo
• Volcanic rocks
• Pleistocene - Holocene (7,930 yBP, ¹⁴C)

• Sedimentary facies: Pyroclastic fall deposit
• Lithofacies: Mafic pyroclastic fall deposit, Rhyolite volcanic ash fall deposit, Mudflow deposit

• Source (Rhyolite volcanic ash fall deposit): Mukaiyama volcano, Shikinejima volcano or Kozushima volcano
• Volume: 0.02 km³
• Thickness: Several m
• Lower limit: Unconformity (Main stratovolcano)

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

• Distribution: Toshima city, Tokyo
• Fossils: Machilus thunbergii

• Isshiki (1978) Geology of the Toshima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 32p. (in Japanese with English abstract 2p.)