Middle Devonian
In the geological timescale, the Middle Devonian epoch (from 397.5 ± 2.7 million years ago to 385.3 ± 2.6 million years ago) occurred during the Devonian period, after the end of the Emsian age.
| Middle Devonian | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chronology | |||||||||||||||||
| |||||||||||||||||
| Etymology | |||||||||||||||||
| Name formality | Formal | ||||||||||||||||
| Usage information | |||||||||||||||||
| Celestial body | Earth | ||||||||||||||||
| Regional usage | Global (ICS) | ||||||||||||||||
| Time scale(s) used | ICS Time Scale | ||||||||||||||||
| Definition | |||||||||||||||||
| Chronological unit | Epoch | ||||||||||||||||
| Stratigraphic unit | Series | ||||||||||||||||
| Time span formality | Formal | ||||||||||||||||
| Lower boundary definition | Fad of the Conodont Polygnathus costatus partitus | ||||||||||||||||
| Lower boundary GSSP | Wetteldorf Richtschnitt, Eifel hills, Germany 50.1496°N 6.4716°E | ||||||||||||||||
| Lower GSSP ratified | 1985 | ||||||||||||||||
| Upper boundary definition | FAD of the Conodont Ancyrodella rotundibola | ||||||||||||||||
| Upper boundary GSSP | Col du Puech de la Suque, Montagne Noire, France 43.5032°N 3.0868°E | ||||||||||||||||
| Upper GSSP ratified | 1986 | ||||||||||||||||
The Middle Devonian epoch is subdivided into two stages: Eifelian and Givetian.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.