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Ama Formation Sugisaki, 1961

• Coherent formation
• Pleistocene (450 - 200 ka)
• Correlation: Shiomisaka Gravel Bed, Tokaen Gravel Bed, Momoyama Gravel Bed

• Sedimentary facies (Am1,3, Upper): Freshwater (Forminifera, Diatoms)
• Sedimentary facies (Am1,3, Middle): Inner bay (Forminifera, Diatoms)
• Sedimentary facies (Am1,3, Lower): Brackish (Forminifera, Diatoms)
• Sedimentary facies (Am1,3, Bottom): Freshwater (Forminifera, Diatoms)
• Sedimentary facies (Ag1,2): Fluvial
• Sedimentary facies (Am1,2,3): Transgression deposit
• Sedimentary facies (Ag1,2): Regression deposit
• Lithofacies (Am3): Clay
• Lithofacies (Ag2): Sands, Gravels
• Lithofacies (Am2): Clay
• Lithofacies (Ag1): Sands, Gravels
• Lithofacies (Am1): Clay

• Thickness: ca. 30 - 150 m
• Upper limit: Unconformity (Second Gravel Formation)

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

• Distribution: Nobi plain, Aichi pref.
• Fossils: Diatoms
• Fossils (Pollen): Abies sp., Acer sp., Alisma sp., Alnus sp., Amatanthaceae, Aneilema sp., Aphananthe sp., Araliceae, Artemisia sp., Betula sp., Buxus sp., Carpinus sp., Carya sp., Castanea sp., Castanopsis sp., Cauduoideae, Celis sp., Cichorioideae, Cyperaceae, Daphniphillum sp., Dinoflegellata sp., cf. Dystylium sp., Ericaceae, Fagus sp., Fraxinus sp., Gramineae, Ilex sp., Juglans sp., Lagerstroemia sp., Ligustrum sp., Liquidambar sp., Lycopodium sp., Menyanthes sp., cf. Metasequoia sp., Mosla sp., Myriophyllum sp., Nupher sp., Osmunda sp., Ostrya sp., Pediastrum sp., Picea sp., Pinus (Diploxylon) sp., Pinus (Haploxylon) sp., Podocarpus sp., Polygonum sp., Polypodiaceae, Potamogeton sp., Pterocarya sp., Quercus (Cyclobalanopsis) sp., Quercus (Lepidobalanus) sp., Ranunculaceae, Rhamnaceae, Rosaceae, Sagittaria sp., Salix sp., Sapium sp., Sciadopitys sp., Sphagnum sp., Styrax sp., Symplocos sp., Taxodiaceae, Thalictrum sp.,Tsuga sp., Ulmus sp., Utricularia, Viburnum sp., Vitis sp., Zelkova sp.
• Tephra: Ata-Torihama tephra (Ata-Th, 240 ka)

• Makinouchi et al. (2013) Jour. Geol. Soc. Japan, vol.119, no.5, pp.335-349 DOI
• Yoshida et al. (1991) Geology of the Kuwana District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 154p. (in Japanese with English abstract 5p.)
• Sakamoto et al. (1986) Geology of the Nagoya-Nambu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 55p. (in Japanese with English abstract 3p.)
• Sakamoto et al. (1984) Geology of the Nagoya-Hokubu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 64p. (in Japanese with English abstract 3p.)
• Takada et al. (1979) Geology of the Tsushima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 56p. (in Japanese with English abstract 5p.)