Triassic was some sort of end-Carnian extinction, when several herbivorous archosauromorph groups died out, while the large herbivorous therapsids—the kannemeyeriid dicynodonts and the traversodont cynodonts—were much reduced in the northern half of Pangaea (Laurasia). These extinctions within the Triassic and at its end allowed the dinosaurs to expand into many niches that had become unoccupied. Dinosaurs became increasingly dominant, abundant and diverse, and remained that way for the next 150 million years. The true "Age of Dinosaurs" is during the following Jurassic and Cretaceous periods, rather than the Triassic. Triassic The Triassic () is a geologic period and system which spans
Orcombe Point cliffs further east. The coastal exposures along the coastline provide a continuous sequence of Triassic, Jurassic and Cretaceous rock formations spanning approximately 185 million years of the Earth's history. The localities along the Jurassic Coast includes a large range of important fossil zones. Orcombe Point is the western end of the Jurassic Coast and the South West Coast Path includes the entire length of the site. The ascent to Orcombe Point shows the successive layers of different sedimentary rocks, which were deposited under varying geological conditions. At the base are cross-bedded sandstones. Towards the top, the rock types are those