| System (period) | Series (epoch) | Stage (age) | Lower boundary, Ma | |
|---|---|---|---|---|
| Paleogene | Paleocene | Danian | 66,0 | |
| Cretaceous | Upper (Late) | Maastrichtian |  72.1±0.2
| |
| Campanian | 83.6±0.2
| |||
| Santonian | 86.3±0.5
| |||
| Coniacian | 89.8±0.3
| |||
| Turonian | 93.9
| |||
| Cenomanian | 100.5
| |||
| Lower (Early) | Albian | ~113.0
| ||
| Aptian | ~121.4 | |||
| Barremian | 125.77* | |||
| Hauterivian | ~132.6
| |||
| Valanginian | ~139.8 | |||
| Berriasian | ~145.0 | |||
| Jurassic | Upper | Tithonian | older | |
| Subdivisions and "golden spikes" according to IUGS as of September 2023[1] *A golden spike is seen in chart but not ratified yet. | ||||
The Berriasian is a first stage of the Cretaceous system, corresponding to the Berriasian age of the Cretaceous period. It lasted from approximately 145 Ma to around 139.8 Ma (million years ago) (IUGS 2023). It is preceded by the Tithonian of the Jurassic and is followed by the Valanginian of the Cretaceous.
Definition[]
As of 2024, there is no GSSP defining the base of the Berriasian and the whole Cretaceous system. As it said by Alekseev A. S. (Lomonosov Moscow State University) in 2013, "the search process and confirmation of the Jurassic-Cretaceous boundary has long become a joke".[2] A candidate is a section at Tré Maroua, southern France, with the base of Calpionella alpina Subzone in the middle of magnetozone M19n.2n for the lower boundary.[3]
Berriasian life[]
The seas were still inhabited by numerous ammonites. Berriasian genera include Protetragonites, Pseudosubplanites, Negreliceras, Raimondiceras, Haplophylloceras and Riasanites. Cartilaginous fish like Polyacrodus, Hybodus, Egertonodus, Parvodus and Planohybodus are known from the Berriasian of Europe. One of the most common bony fish was Lepitotes. Turtles like pleurostenid Desmemys lived in estuaries and sea bays. The same ecosystems were inhabited by plesiosaurs like Gronausaurus, Brancasaurus and Hastanectes. Fresh water bodies were inhabited by frogs (Sunnybatrachus) and salamanders (Apricosiren). Various crocodylomorphs like Nannosuchus and Goniopholis also lived there. The marsh long-snouted Pholidosaurus fed on small fish and amphibians.
Vegetation along the banks of lagoons, rivers and swamps attracted various dinosaurs. Dacentrurus, a stegosaurid, defended themselves from predators with its spikes, Hylaeosaurus and Vectipelta were covered with strong armor, while Hypsilophodon could only rely on the ability to run quickly. During this age, large ornithopods like Iguanodon and Mantellisaurus already appeared. The number of small theropods, such as Dromaeosauroides, has increased. The areas near water bodies were also home to a variety of mammals, such as Thereuodon, Spalacotherium, Magnimus, Peramus, Sunnyodon and Tinodon.
References[]
- ↑ "Latest version of international chronostratigraphic chart". International Commission on Stratigraphy. https://stratigraphy.org/chart#latest-version.
- ↑ Alekseev A. S. (2013) "Current state of International Stratigraphic Chart: Positive and negative consequences for the general stratigraphic scale of Russia". (in Russian) General stratigraphic scale of Russia: current state and ways of perfection. All-Russian meeting. Page 11. ISBN 978-5-98709-394-8 Archived copy
- ↑ "GSSP Table - Mesozoic Era". https://timescalefoundation.org/gssp/index.php?parentid=35.