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Which stages make up the Pennsylvanian Subperiod?
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Carboniferous Period
Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the late Carboniferous Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
The Pennsylvanian Subperiod is formally divided into four depositional stages, which also correspond to specific time units (ages). These stages are as follows:
- Bashkirian: 323.2 to 315.2 million years ago1
- Moscovian: 315.2 to 307 million years ago1
- Kasimovian: 307 to 303.7 million years ago1
- Gzhelian: 303.7 to 298.9 million years ago1
Together, these stages constitute the Pennsylvanian Subsystem, which spans from 323.2 to 298.9 million years ago.12