geologic timescale

n. chronological scale of the history of Earth used to measure the relative or definite age of any section of geologic time

The geological time scale is used by geologists and other scientists to describe the timing and relationships between events that have occurred during the history of Earth. The table of geologic periods presented here agrees with the dates and nomenclature proposed by the International Commission on Stratigraphy, and uses the standard color codes of the United States Geological Survey.
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