Triassic Period FACT FILE

The Triassic /traɪˈæsɪk/ is a geologic period and system that extends from about 250 to 200 Mya (252.2 ± 0.5 to 201.3 ± 0.2 million years ago).

The Triassic began in the wake of the Permian–Triassic extinction event.


The end of the period was marked by yet another major mass extinction, the Triassic-Jurassic extinction event.

The Triassic marked the rise of the reptiles; notably the archosaurs (ruling lizards) and therapsids (mammal-like reptiles).


The archosaurs held the evolutionary edge, over the therapsids and evolving by the middle Triassic into the dinosaurs


The BBC Nature website has a very good section on the Triassic.  


Use this button to visit the BBC Nature website:

The British Geological Survey website has an excellent section on the Triassic environment.  


Use this button to visit the BGS website:

*Based on 'The Geologic Time Scale 2012' by F M Gradstein, J G Ogg, M Schmitz & G Ogg (2012), with additions. Credit: British Geological Survey