Of or from the geologic strata above the Permian and below the Jurassic; of or belonging to the period 250 to 200 million years ago when these strata were laid down.

(geology) A geologic period within the Mesozoic era, comprising lower, middle and upper epochs from about 250 to 200 million years ago.

(geology) In which the characteristics of the Jurassic and Triassic periods appear to be blended.

(evolutionary theory, geology) A volcanic mass extinction at the end of the Permian period 251.9 million years ago.

Synonym of Triassic-Jurassic extinction event.

(evolutionary theory, geology) Synonym of Permian-Triassic extinction

A mass extinction between the Triassic and Jurassic periods 201.3 million years ago.