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Bifrons zone

General information
Lower boundary: equal to 182 Ma (based on Planulata)
Upper boundary: before 175.6 Ma (based on Herangi)
Continent: Europe
See collections within this interval
See map of collections within this interval
Key correlations
Period: Jurassic
Epoch: Early/Lower Jurassic
Stage: Toarcian
10 million year bin: Jurassic 3
Shares base with
Overlaps with
  • Middle Toarcian (182.0 to 175.6 Ma)
  • Levesquei (182.0 to 175.6 Ma)
  • Variabilis (182.0 to 175.6 Ma)
  • Interval name: