The Triassic is the earliest Mesozoic period, approximately to million years ago.[ref]
International Chronostratigraphic Chart by International Commission on Stratigraphy (2026-06). Triassic row
It precedes the Jurassic. In a local sedimentary rock sequence, a missing part of this interval may reflect nondeposition or later erosion; the absence of a named interval in one section does not imply that no time elapsed there. New to topics? Read the docs here!