Ypresian
| Ypresian | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Earth ~50 mya | |||||||||||||
Klondike Mountain Formation, Republic, Washington | |||||||||||||
| Chronology | |||||||||||||
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| Formerly part of | Tertiary Period/System | ||||||||||||
| Etymology | |||||||||||||
| Name formality | Formal | ||||||||||||
| Usage information | |||||||||||||
| Celestial body | Earth | ||||||||||||
| Regional usage | Global (ICS) | ||||||||||||
| Time scale(s) used | ICS Time Scale | ||||||||||||
| Definition | |||||||||||||
| Chronological unit | Age | ||||||||||||
| Stratigraphic unit | Stage | ||||||||||||
| First proposed by | Dumont | ||||||||||||
| Time span formality | Formal | ||||||||||||
| Lower boundary definition | Strong negative anomaly in δ13C values at the PETM | ||||||||||||
| Lower boundary GSSP | Dababiya section, Luxor, Egypt 25°30′00″N 32°31′52″E / 25.5000°N 32.5311°E | ||||||||||||
| Lower GSSP ratified | 2003 | ||||||||||||
| Upper boundary definition | FAD of the calcareous nannofossil Blackites inflatus | ||||||||||||
| Upper boundary GSSP | Gorrondatxe section, Western Pyrenees, Basque Country, Spain 43°22′47″N 3°00′51″W / 43.3796°N 3.0143°W | ||||||||||||
| Upper GSSP ratified | April 2011 | ||||||||||||
In the geologic timescale the Ypresian is the oldest age or lowest stratigraphic stage of the Eocene. It spans the time between 56 and 48.07 Ma, is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian is consistent with the Lower Eocene (Early Eocene).