251–199.6 ẹgbẹgbẹ̀rún ọdun sẹ́yìn
|Mean atmospheric O2 content over period duration||ca. 16 Vol %
(80 % of modern level)
|Mean atmospheric CO2 content over period duration||ca. 1750 ppm
(6 times pre-industrial level)
|Mean surface temperature over period duration||ca. 17 °C
(3 °C above modern level)
The Triassic is a geologic period that extended from about 250 to 200 Mya (million years ago). As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events. The extinction event that closed the Triassic Period has recently been more accurately dated, but as with most older geologic periods, the rock beds that define the start and end are well identified, but the exact dates of the start and end of the period are uncertain by a few million years.
During the Triassic, both marine and continental life show an adaptive radiation beginning from the starkly impoverished biosphere that followed the Permian-Triassic extinction. Corals of the hexacorallia group made their first appearance. The first flying vertebrates, the pterosaurs, evolved during the Triassic.
|Àyọkà yìí tàbí apá rẹ̀ únfẹ́ àtúnṣe sí.
|Lower/Early Triassic||Middle Triassic||Upper/Late Triassic|
|Induan | Olenekian||Anisian | Ladinian||Carnian | Norian
|Preceded by Proterozoic Eon||542 Ma - Phanerozoic Eon - Present|
|542 Ma - Paleozoic Era - 251 Ma||251 Ma - Mesozoic Era - 65 Ma||65 Ma - Cenozoic Era - Present|