International Chronostratigraphic Chart
http://www.icgc.cat
> Geologic map > International Chronostratigraphic Chart
International Chronostratigraphic Chart
The international Chronostratigraphic Chart describes the geological time in the history of the Earth. It combines a numerical sca
scale) and a scale is expressed in units of time relative (cronostratigraphic scale).
The cronostratigraphic scale set by convention and is based on the International System of Standardized stratigraphic units (eg
of ammonites Hildoceras bifrons"). This system, which is regulated by the International Commission on Stratigraphy (ICS in
the divisions of geologic time (eons, eras and their subdivisions), establishes the boundaries of units and calibrated chronometri
correspond to them.
The lower limits of the ranges of all units (stages, series, systems and eratemas) are currently in the process of being defined b
Stratotypes Limit (GSSP-Global stratotype Section and Boundary Point).
The Archean and Proterozoic by convention chronometrically were defined as absolute numerical age (Global Standard Stratigra
the above process.
GSSP officers listed in the table with the symbol of "Golden Nail" (Golden Spike) to also materialize on the ground. You can find
of the GSSP ratified (criteria defining each geographical and geological location, correlation, etc.) at http://www.stratigraphy.org.
Numerical ages (Ma) are subject to review and do not define units in the Phanerozoic and the Ediacariense. That will only make
boundaries of those units Fanerozoic have not yet ratified GSSP, or which does not have a bounded numerical age, the table giv
(~).
Numerical ages of all systems except the Triassic, Cretaceous and Precambrian, are from Gradstein et al. (A Geologic T
The ages of the Lower Pleistocene, Triassic and Cretaceous were provided by the relevant ICS subcomissions.
Coloring follows the Comission for the Geological Map of the World (http://www.ccgm.org).
Chart designed per K. M. Cohen, S.C. I P. L. Finney Gibbard, January 2013 © International Commission on
Latest version of the International Chronostratigraphic Chart
Last version in english v2015/01, Size A3: Format pdf 71 Kb,
Format jpg 1,6 MB
07/09/15 10:47:29