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Which geologic period came before the Ordovician Period?
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Ordovician Period
The distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the Ordovician Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
The Cambrian Period is the geologic period that immediately preceded the Ordovician Period. The Ordovician Period began 485.4 million years ago, following the conclusion of the Cambrian, and lasted until the start of the Silurian Period 443.8 million years ago.1