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Byobugaura Formation (Makiyama, 1930) Kanto Quaternary Research Group, 1974

Invalid synonym: Taya Formation (Lower part is Naganuma Formation)

• Type locality: Isogo, Isogo ward, Yokohama city, Kanagawa prefecture
• Coherent formation
• Sediments by Byobugaura transgression
• Pleistocene

• Sedimentary facies: Marine
• Sedimentary facies: Inner bay
• Sedimentary facies: Sagami Sedimentary Basin-fill deposit
• Climate: Warn temperate (Evergreen broad-leaved forests), Cool temperate (Deciduous broad-leaved forests)
• Lithofacies (Upper): Sands
• Lithofacies (Upper, Minor): Mud
• Lithofacies (Middle): Scoriaceous tuff
• Lithofacies (Lower): Sands
• Lithofacies (Bottom): Peat mud

• Thickness: ca. 36 - 60 m
• Upper limit: Conformity (Hirato Loam), Unconformity (Kamikurata Formation, Sannodai Loam, Maioka Formation)
• Lower limit: Unconformity (Naganuma Formation)

• Distribution: Isogo ward, Yokohama city, Kanagawa pref..; Kanai town - Totsuka town - Shimokurata town - Nase town, Totsuka ward, Yokohama city, Kanagawa pref.; Noba town - Hino town - Kamioka, Konan ward, Yokohama city, Kanagawa pref.; Bessho town, Minami ward, Yokohama city, Kanagawa pref.
• Fossils (Shellfishes): Anadara granosa, Crassostrea gigas, Cyclina chinensis, Macoma incongrua, Batillaria zonaris, Saxidomus purpulatus
• Fossils (Plants): Abies cf. firma, Acer mono, Acer palmatum var. palmatum, Actinodophna lancifolia, Akebia cf. quinata, Alnus cf. sieboldiana, Carpinus cordata, Carpinus japonica, Carpinus laxiflora, Carpinus tschonoskii, Castanopsis cuspidata, Cinnamomum cf. camphora, Cinnamomum japonicum, Cleyera japonica, Cornus kousa, Cryptomeria japonica, Deutzia sp., Distylium racemosum, Eurya japonica, Fagus crenata, Fagus cf. hayatae, Fagus japonica, Ficus cf. erecta, Fraxinus sp., Hamameris sp., Hydrangea sp., Illicium religiosum, Katopanax septemlobus, Lindera sp., Machilus thunbergii, Magnolia cf. obovata, Neolitsea cf. sericea, Onychium cf. japonicum, Ostrya japonica, Polygonum sp., cf. Pseudotsuga japonica, Quercus acuta, Quercus acutissima (or Q. variaviris), Quercus glauca, Quercus myrsinaefolia, Quercus salicina, Quercus serrata, Quercus sessilifolia, Rhus sp., Rumex cf. acetosa, Saphindus? sp., Sasa? sp., Tilia sp., Torreya nucifera, Tsuga cf. sieboldii, Wisteria floribunda, Zelkova serrata
• Tephra: SmP, Cr

• Oka et al. (1984) Geology of the Tokyo-Seinambu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 148p. (in Japanese with English abstract 7p.)
• Mitsunashi and Kikuchi (1982) Geology of the Yokohama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 105p. (in Japanese with English abstract 4p.)
• Oka et al. (1979) Geology of the Fujisawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 111p. (in Japanese with English abstract 5p.)