Geologic Unit Name	Yamaga Formation(5030)	Age	Early Oligocene series	Distribution Area(2nd Mesh Cord)		503064, 503066
Mesh Cord	Map/5030	Explanatory Notes	O2	Mesh Cord		Explanatory Notes
Mesh Cord		Explanatory Notes		Mesh Cord		Explanatory Notes
Thickness	About 200-330 m in Kitakyushushi west to Ashiyamachi district (thickness of Korosue Mudstone Member and Orio sandstone) and thicker in south. More than 150 m though base faulted in Yofukuji in Ogura map district. Estimated to be about 110-120 m though top uncertain in Ainoshima, Shimonosekishi west to Kitakyushushi northern district.
Rock Facies	Mudstone and sandstone with basal conglomerate.
Type Locality	Near Yamaga, northeast Ashiyamachi, Ongagun in Orio map district. Northwest Taya to Kariomisaki cape, Ashiyamachi, Kitakyushushi. Ainoshima in Ogura map district. Orio Sandstone Formation exposes between Korosue, Mizumakimachi, Ongagun and JR Orio Station in Yahatanishiku, Kitakyushushi.
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