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The Devonian (/dəˈvoʊni.ən, dɛ-/ də-VOH-nee-ən, deh-) is a geologic period and system of the Paleozoic era during the Phanerozoic eon, spanning 60.7 million years from the end of the preceding Silurian period at 419.62 million years ago (Ma), to the beginning of the succeeding Carboniferous period at 358.86 Ma. It is the fourth period of both the…
History, Geography & Regions
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| Subject | Predicate | Object | Confidence | Src |
|---|---|---|---|---|
| Devonian | Celestial body | Earth | 1.00 | infobox |
| Devonian | Chronological unit | Period | 1.00 | infobox |
| Devonian | Lower boundary definition | FAD of the Graptolite Uncinatograptus uniformis | 1.00 | infobox |
| Devonian | Lower boundary GSSP | Klonk, Czech Republic .mw-parser-output .geo-default,.mw-parser-output .geo-dms,.mw-parser-output .geo-dec{display:inline}.mw-parser-output .geo-nondefault,.mw-parser-output .ge… | 1.00 | infobox |
| Devonian | Lower GSSP ratified | 1972 | 1.00 | infobox |
| Devonian | Name formality | Formal | 1.00 | infobox |
| Devonian | Nickname(s) | Age of Fishes | 1.00 | infobox |
| Devonian | Regional usage | Global (ICS) | 1.00 | infobox |
| Devonian | Sea level above present day | Relatively steady around 189 m, gradually falling to 120 m through period | 1.00 | infobox |
| Devonian | Stratigraphic unit | System | 1.00 | infobox |
| Devonian | Time scale(s) used | ICS Time Scale | 1.00 | infobox |
| Devonian | Time span formality | Formal | 1.00 | infobox |
| Devonian | Upper boundary definition | FAD of the Conodont Siphonodella sulcata (discovered to have biostratigraphic issues as of 2006). | 1.00 | infobox |
| Devonian | Upper boundary GSSP | La Serre, Montagne Noire, France 43°33′20″N 3°21′26″E / 43.5555°N 3.3573°E / 43.5555; 3.3573 | 1.00 | infobox |
| Devonian | Upper GSSP ratified | 1990 | 1.00 | infobox |
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