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Related to Pennsylvanian period: Permian period, Mississippian Period, Carboniferous period, Upper Carboniferous, Upper Pennsylvanian
In North America, the second part of what is generally called the Carboniferous period: 320 to 286 million years ago.
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|Noun||1.||Pennsylvanian period - from 310 million to 280 million years ago; warm climate; swampy land|
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