[ Top ] [ Japanese ]

Amura Formation (Tashiro et al., 1986)

Invalid synonym: Upper half of III Formation

• Type locality: east seashore of Amura, Matsushima village, Kamiamakusa city, Kumamoto prefecture
• Coherent formation
• Late Cretaceous, Campanian (Inoceramus sp.)

• Sedimentary facies: Marine
• Sedimentary facies: Channel, Leeve
• Lithofacies (Upper): Mudstone-dominant interbedded sandstone and mudstone
• Lithofacies (Lower): Sandstone
• Lithofacies (Minor): Tuff
• Sedimentary structures (Upper): Slump structures
• Sedimentary structures (Lower): Cross stratification, Parallel stratification, Convolute lamination

• Thickness: 15 - 150 m
• Upper limit: Unconformity (Akasaki Formation)

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

• Distribution: Amura - Iwajima island - Maejima island - Nakajima island - Seshima island, Matsushima village, Kamiamakusa city, Kumamoto pref.; Tobasejima island, Uki city, Kumamoto pref.
• Fossils: Ammonoids, Crinoids, Plants, Radiolarians
• Fossils (Bivalves): Miltha sp., Nucula amanoi, Periploma sp., Solemya angusticaudata, Inoceramus higoensis, Sphenoceramus nagaoi

• Kojo et al. (2011) Jour. Geol. Soc. Japan, vol.117, no.7, pp.398-416 DOI