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Which organization officially ratified the modern beginning of the Quaternary Period in 2009?
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Quaternary
Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the Quaternary Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
In 2009, the International Union of Geological Sciences (IUGS) officially ratified the decision to set the beginning of the Quaternary Period at 2,588,000 years ago.1
This decision formally designated the Quaternary as the uppermost period of the Cenozoic Era, aligning its start with the beginning of the Gelasian Age. This ratification followed a period of debate regarding the classification of the Quaternary and the Pleistocene Epoch within the geologic time scale.1