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Muro Pyroclastic Flow Deposit (Shiida et al., 1960) Nishioka et al., 1998

Synonym: Muro volcanos, Muro Ignimbrite

Synonym (Basal facies): Furono Formation

It had been considered a member of Setouchi Volcanic Rocks.

• Type locality: Shorenjigawa river, Igami - Mount Kurosoyama, Soni city, Uda county, Nara prefecture
• Outflow deposit from a caldera volcano
• Volcanic rocks
• Miocene (16 - 13.5 Ma, K-Ar; 15.7 - 14.9 Ma, FT; 14.3 Ma, Ar-Ar)
• Correlation (Marginal facies): Sekibutsu Tuff Member, Tamateyama Tuff Bed, Furudera Tuff
• Correlation: Kbi, Kn-1?

• Sedimentary facies: Terrestrial
• Lithofacies: Pyroclastic flow deposit (A cooling unit)
• Lithofacies: Garnet-bearing orthopyroxene-biotite rhyolite - dacite welded volcanic lapilli tuff
• Lithofacies (Minor): Obsidian, Volcanic ash
• Lithofacies (Accidental fragments): None
• Lithofacies (Basal facies): Volcanic ash, Tuff breccia
• Lithofacies (Basal facies, Accidental fragments): Chert, Mudstone
• Sedimentary structures: Columnar joints

• Source: central - eastern Kii peninsula (Kumano Acidic Rocks or Odai caldera)
• Mode of eruption: Plinian
• Eruptive volume (Present): ca. 62 km³
• Eruptive volume (Original): 100 km³ or more
• Thickness (Overall): ca. 250 - 400 m
• Thickness (Basal): 20 m or thinner
• Distribution (East-West): ca. 28 km
• Distribution (South-North): ca. 15 km
• Running distance: 50 km or more
• Lower limit: Conformity (Onomi Conglomerate Member), Unconformity (Ryoke Metamorphic Rocks, Granite)

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

• Distribution: Igami - Mount Kurosoyama - Byobu-iwa - Kabutoiwa - Mount Yoroidake - Mount Sumitsukayama, Soni city, Uda county, Nara pref.; Lake Muroko, Uda city, Nara pref.; Hayama - Yadawara town, Nara city, Nara pref.; Kaochidani valley - Akame-Shijuhachiaki fall, Nabari city, Mie pref.; Mount Oborayama - Mount Amagadake, Misugi town, Tsu city, Mie pref.

• Sato et al. (2012) Jour. Geol. Soc. Japan, vol.118, Supplement, pp.53-69 DOI
• Shinjoe et al. (2010) Jour. Geol. Soc. Japan, vol.116, no.8, pp.447-452 DOI
• Iwano et al. (2009) Jour. Geol. Soc. Japan, vol.115, no.8, pp.427-432 DOI
• Yamashita et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.7, pp.340-352 DOI
• Iwano et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.7, pp.326-339 DOI
• Shinjoe et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.7, pp.310-325 DOI
• Nishioka et al. (2001) Geology of the Sakurai District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 141p. (in Japanese with English abstract 5p.)
• Ozaki et al. (2000) Geology of the Nara District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 162p. (in Japanese with English abstract 5p.)
• Nishioka et al. (1998) Geology of the Nabari District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 72p. (in Japanese with English abstract 5p.)