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When did the Cretaceous Period begin and end?
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Cretaceous Period
Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the late Cretaceous Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
The Cretaceous Period began 145 million years ago and ended 66 million years ago. As the final period of the Mesozoic Era, it is the longest period of the Phanerozoic Eon, spanning a total of 79 million years.12