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Which stages make up the Upper Devonian Series?
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Devonian Period
Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the early Devonian Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
The Upper Devonian Series, which spans from approximately 382.7 million to 358.9 million years ago, is composed of two standard stages:1
- Frasnian Stage: The lower stage of the Upper Devonian, defined by the first occurrence of the conodont Ancyrodella rotundiloba.21
- Famennian Stage: The upper stage of the series, which begins following the mass extinction event known as the Upper Kellwasser Event.21