Koyamada Fm
Period:
Jurassic
Age Interval:
Late Jurassic (Tithonian), (8i)
Province:
South Kitakami Belt-Central Sub-belt
Type Locality and Naming
the Karakuwa-Oshika Sub-belt; Soma District
Synonym:
Lithology and Thickness
dominated by clastic rocks
Lithology Pattern:
Coarse clastics
Relationships and Distribution
Lower contact
Regionally, the schematic strat column indicates the next older unit as Nakanosawa Fm
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Somanakamura Gr
Regional extent
GeoJSON
null
Fossils
Ammonoid fauna
Age
Late Jurassic (Tithonian)
Age Span:
Beginning stage:
Tithonian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
149.24
Ending stage:
Berriasian
Fraction up in the ending stage:
1.0
Ending date (Ma):
137.70
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Moreno, T., WALLIS, S., Kojima, T. & Gibbons, W. (Eds) 2016. The Geology of Japan. Geological Society. London. 1-24.