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Shiga Lake Deposit (Iijima, 1956) Akahane and Akai, 1975

• Type locality: Ishinoyu hot spring, Yamanouchi city, Shimoakai county, Nagano prefecture
• Coherent formation
• Dammed lake deposit formed twice in pre-Kakuma river by Older Shigayama Volcanic Rocks
• middle - late Pleistocene (same time as Yokoyugawa Lake Deposit)

• Sedimentary facies (Upper): Fluvial
• Sedimentary facies: Lacustrine
• Lithofacies (Upper): Sands, Gravels, Volcanic ash
• Lithofacies (Middle): Volcanic ash-rich silt
• Lithofacies (Middle, Minor): Volcanic ash, Interbedded silt and sands
• Lithofacies (Lower): Sands, Gravels
• Lithofacies (Lower, Minor): Volcanic ash-rich silt, Sands, Peat

• Thickness: ca. 20 - 55 m
• Thickness (Upper): 20 m
• Thickness (Middle): 12 m
• Thickness (Lower): 25 m
• Lower limit: Abut unconformity (Takai Volcanic Rocks, Suzurikawa Volcanic Rocks, Older Shigayama volcanic Rocks, Intrusive rocks)

• Distribution: Ishinoyu hot spring - Hiratoko - Tanohara - Kumanoyu hot spring, Yamanouchi city, Shimotakai county, Nagano pref.
• Fossils: Wood fragments

• Akahane et al. (1992) Geology of the Nakano District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 106p. (in Japanese with English abstract 4p.)