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Mita Formation Naemura and Shimada, 1984

• Coherent formation
• early Miocene
• Intruded by: Oyama Quartz Syenite, Syenite porphyry dike
• Correlation: Kori Formation, Koura Formation

• Sedimentary facies: Freshwater, Brackish
• Sedimentary facies (Upper): Delta, Sand bar
• Sedimentary facies (Middle): Shoreline, River deposits
• Sedimentary facies (Lower): Alluvial fan facing shallow water
• Sedimentary facies (Lower, Minor): Shallowwater
• Sedimentary facies (Lower): Gravity flow
• Lithofacies (Upper): Felsic tuff, Tuffaceous sandstone, Siltstone, Shale
• Lithofacies (Middle): Tuffaceous sandstone, Shale
• Lithofacies (Middle, Minor): Conglomerate
• Lithofacies (Lower): Andesite volcanic conglomerate, Lapilli tuff, Tuff
• Lithofacies (Lower, Minor): Tuffaceous conglomerate, Sandstone, Siltstone
• Lithofacies (Minor): Hornfels
• Sedimentary structures (Upper): Parallel stratification, Trough cross-stratification
• Sedimentary structures (Middle): Graded bedding, Wave ripples, Low-angle cross-stratification, Wavy cross-stratification, Parallel stratification
• Sedimentary structures (Lower): Graded bedding, Wave ripples, Low-angle cross-stratification, Parallel stratification

• Thickness: 600 m or thicker
• Thickness (Lower): 8.5 - 17 m
• Upper limit: Unconformity (Ichibu Formation, Takuhiyama Pyroclastic Cone)

• Distribution: Mita dam - Beppu - Oyama, Nishinoshima city, Oki county, Shimane pref.
• Fossils (Shellfishes): Thyasira bisecta, Viviparus
• Fossils (Daijima-type flora): Alangium cf. aequalifolium, Alnus sp., Equisetum sp., Ulmus sp.

• Chiba et al. (2000) Geology of the Urago District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 74p. (in Japanese with English abstract 3p.)