International Commission on Stratigraphy

Remane J., Bassett M. G., Cowie J. W., Gohrbandt K. H., Lane R., Michelsen O., and Naiwen W. (1996) Revised guidelines for the establishment of global chronostratigraphic standards by the international commission on stratigraphy. Episodes 19, 77-81. 

It is followed the geological time scale as determined by the International Commission on Stratigraphy (ICS). The ICS has not finished its job and gaps remain, particularly in the Early Paleozoic. Where gaps occur, it is generally followed the Russian system for the Cambrian and the British system for the Silurian. Epochs are subdivided further into ages not listed here. The periods from Cretaceons and older are subdivided into epochs and ages not shown here. 

Hofmann AW, White WM (1982) Mantle plumes from ancient oceanic crust. Earth Planet Sci Lett 57 421 36 lUGS (2002) International stratigraphic chart. International Commission on Stratigraphy. UNESCO, New York... 

The dates shown on this geological timescale were specified by the International Commission on Stratigraphy in 2009. 

Cowie, J.W. and Bassett, M.G. (1989) Global stratigraphic chart, with geochronometric and magnetostratigraphic calibration. Bureau of International Commission on Stratigraphy-International Union of Geological Sciences. 

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