East Oshima chert Fm
Period:
Jurassic, Triassic
Age Interval:
Province:
Hokkaido
Type Locality and Naming
Rebun-Kabato Sub-belt and Oshima Belt
Synonym:
Lithology and Thickness
Chert
Lithology Pattern:
Chert
Relationships and Distribution
Lower contact
Oshima Carboniferous-Permian limestone Fm (conformable) in West Oshima Belt; shima Trassic limestone Fm (conformable) in East Oshima Belt.
Upper contact
East Oshima clastics Fm (conformable)
Regional extent
Rebun-Kabato Sub-belt and Oshima Belt
GeoJSON
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Fossils
Age
Based on radiolarians and conodonts, the age of chert ranges from Late Carboniferous or Early Permian to Early Jurassic (Tajika et at.1984; Ishiga & Ishiyama 1987).
Age Span:
Beginning stage:
Norian
Fraction up in beginning stage:
0.455
Beginning date (Ma):
217.49
Ending stage:
Oxfordian
Fraction up in the ending stage:
0
Ending date (Ma):
161.53
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Hayato Ueda. 2g Hokkaido. in Moreno, T., WALLIS, S., Kojima, T. & Gibbons, W. (Eds) 2016. The Geology of Japan. Geological Society. London. 201-220.