The interval definitions in this timescale are derived from the following sources:

• W. B. Harland, R. L. Armstrong, A. V. Cox, L. E. Craig, A. G. Smith and D. G. Smith. 1990. A Geologic Time Scale 1989. view
• F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
• M. Freudenthal. 2006. Mammal Paleogene zones. personal communication view
• F. J. Prevosti, C. O. Romano, A. M. Forasiepi, S. Hemming, R. Bonini, A. M. Candela, E. Cerdeño, M. C. Madozzo Jaén, P. E. Ortiz, F. Pujos, L. Rasia, G. I. Schmidt, M. Taglioretti, R. D. E. MacPhee, and U. F. J. Pardiñas. 2021. New radiometric 40Ar–39Ar dates and faunistic analyses refine evolutionary dynamics of Neogene vertebrate assemblages in southern South America. Scientific Reports 2021(11):9830 view
• J. J. Flynn and C. C. Swisher, III. 1995. Cenozoic South American Land Mammal Ages: correlation to global geochronology. Geochronology Time Scales and Global Stratigraphic Correlation, SEPM Special Publication 54:317-333 view

There are 13 timescales which overlap this one. show

• Obsolete Names for ICS Units
• Ten Million Year Bins
• European Faunal Units
• European Faunal Zones
• Mammal Paleogene Zones
• Cenozoic Subepochs of Southern Europe
• Central Paratethys Stages
• Neogene Mammal Ages of China
• Paleogene Mammal Ages of Asia
• North American Land Mammal Ages
• North American Mammal Subages/Zones
• South American Land Mammal Ages
• Cretaceous-Cenozoic of New Zealand

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 13393 collections