Santonian Explained
| Santonian |
| Color: | Santonian |
| Time Start: | 86.3 |
| Time Start Uncertainty: | 0.5 |
| Time End: | 83.6 |
| Time End Uncertainty: | 0.2 |
| Timeline: | Cretaceous |
| Name Formality: | Formal |
| Celestial Body: | earth |
| Usage: | Global (ICS) |
| Timescales Used: | ICS Time Scale |
| Chrono Unit: | Age |
| Strat Unit: | Stage |
| Timespan Formality: | Formal |
| Lower Boundary Def: | FAD of the Inoceramid Bivalve Cladoceramus undulatoplicatus |
| Lower Gssp Location: | Olazagutia, Spain |
| Lower Gssp Accept Date: | January 2013[1] |
| Upper Boundary Def: | Base of Chron C33r[2] |
| Upper Gssp Location: | Bottaccione, Gubbio, Italy |
| Upper Gssp Coords: | [3] |
| Upper Gssp Accept Date: | October 2022[4] |
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 86.3 ± 0.7 mya (million years ago) and 83.6 ± 0.7 mya. The Santonian is preceded by the Coniacian and is followed by the Campanian.[5]
Stratigraphic definition
The Santonian Stage was established by French geologist Henri Coquand in 1857. It is named after the city of Saintes in the region of Saintonge, where the original type locality is located.
The base of the Santonian Stage is defined by the appearance of the inoceramid bivalve Cladoceramus undulatoplicatus. The GSSP (official reference profile) for the base of the Santonian Stage is located near Olazagutia, Spain; it was ratified by the Subcommission on Cretaceous Stratigraphy in 2012.[6] The Santonian's top (the base of the Campanian Stage) is informally marked by the extinction of the crinoid Marsupites testudinarius.[7] A GSSP for the top of the Santonian was ratified in October 2022 in Bottaccione, Gubbio, Italy.[2]
Subdivision
The Santonian is sometimes subdivided into Lower, Middle and Upper Substages. In the Tethys domain the Santonian is coeval with a single ammonite biozone: that of Placenticeras polyopsis. Biostratigraphy based on inoceramids, nanoplankton or forams is more detailed.
References
Notes
- Lamolda . M. . Paul . C. . Peryt . D. . Pons . J. . The Global Boundary Stratotype and Section Point (GSSP) for the base of the Santonian Stage, "Cantera de Margas", Olazagutia, northern Spain . Episodes . March 2014 . 37 . 1 . 2–13 . 10.18814/epiiugs/2014/v37i1/001 . 24 December 2020. free .
- Jarvis . Ian . etal . Carbon isotopes, palynology and stratigraphy of the Santonian–Campanian boundary: The GSSP auxiliary sections, Seaford Head (England) and Bocieniec (Poland), and correlation between the Boreal and Tethyan realms . Cretaceous Research. 2023 . 143 . 105415 . 10.1016/j.cretres.2022.105415 . 2023CrRes.14305415J . 253436620 . free . 10871/133015 . free .
- The Global Boundary Stratotype Section and Point (GSSP) of the Campanian Stage at Bottaccione (Gubbio, Italy) and its Auxiliary Sections: Seaford Head (UK), Bocieniec (Poland), Postalm (Austria), Smoky Hill, Kansas (U.S.A), Tepayac (Mexico) . Episodes . 1 February 2023 . 6 . 10.18814/epiiugs/2022/022048 . 27 March 2023 . Gale . Andy . Batenburg . Sietske . Coccioni . Rodolfo . Dubicka . Zofia . Erba . Elisabetta . Falzoni . Francesca . Haggart . Jim . Hasegawa . Takishi . Ifrim . Christina . Jarvis . Ian . Jenkyns . Hugh . Jurowska . Agata . Kennedy . Jim . Maron . Matteo . Muttoni . Giovanni . Pearce . Martin . Petrizzo . Maria Rose . Premoli-Silva . Isabella . Thibault . Nicolas . Voigt . Silke . Wagreich . Michael . Walaszczyk . Irek . 46 . 3 . 256539746 . 2434/968946 . free .
- Web site: Campanian GSSP Ratified by IUGS . Subcommission on Cretaceous Stratigraphy . International Commission on Stratigraphy . 14 January 2023.
- Gradstein et al. (2004)
- Book: Geologic Time Scale 2020 . Elsevier . 2020 . F.M. . Gradstein . J.G. . Ogg . M.D. . Schmitz . G.M. . Ogg . 1038 . 978-0-12-824360-2.
- Book: Geologic Time Scale 2020 . Elsevier . 2020 . F.M. . Gradstein . J.G. . Ogg . M.D. . Schmitz . G.M. . Ogg . 1040 . 978-0-12-824360-2.
Literature
- 2004: A Geologic Time Scale 2004, Cambridge University Press.
External links
