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Which seven stages make up the Ordovician System?
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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 Ordovician System is divided into seven stages, which were established by the International Commission on Stratigraphy to provide a global correlation of stratigraphic and fossil markers. These stages are organized by epoch as follows:1
- Early Ordovician Epoch
- Tremadocian (Stage 1)
- Floian (Stage 2)
- Middle Ordovician Epoch
- Dapingian (Stage 3)
- Darriwilian (Stage 4)
- Late Ordovician Epoch
- Sandbian (Stage 5)
- Katian (Stage 6)
- Hirnantian (Stage 7)1