Santonian
| Santonian | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Chronology | |||||||||
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| 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 | ||||||||
| Time span formality | Formal | ||||||||
| Lower boundary definition | FAD of the Inoceramid Bivalve Cladoceramus undulatoplicatus | ||||||||
| Lower boundary GSSP | Olazagutia, Spain 42°52′00″N 2°11′48″W / 42.8668°N 2.1968°W | ||||||||
| Lower GSSP ratified | January 2013 | ||||||||
| Upper boundary definition | Base of Chron C33r | ||||||||
| Upper boundary GSSP | Bottaccione, Gubbio, Italy 43°21′46″N 12°34′58″E / 43.3627°N 12.5828°E | ||||||||
| Upper GSSP ratified | October 2022 | ||||||||
The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 85.7 ± 0.2 mya (million years ago) and 83.6 ± 0.2 mya. The Santonian is preceded by the Coniacian and is followed by the Campanian.