Alaska Museum of Natural History

Geologic Time Scale - Mesozoic Era

(64.5 million years ago to 250 million years ago)

ERA	PERIOD	EPOCH	DATES	AGE of	Events
Cenozoic
Mesozoic	Cretaceous		64.5-144	Hadrosaurid (a) (b) (c), hypsilophodontid, ceratopsian, theropod (a) (b) (c), and ankylosaur dinosaurs.	Flowering plants
	Jurassic		144-208	Plesiosaur marine reptiles and theropods.	1st birds/mammals
	Triassic		208-250	Ichthyosaur marine reptiles live in Alaska.	First Dinosaurs
Paleozoic	"Pre-Mesozoic"
Precambrian	"Pre-Mesozoic"

Note: Dates are in millions of years

Modified from University of Alaska-Fairbanks, Geoscience Web Site

Taken from: MODERN PHYSICAL GEOLOGY, Graham R. Thompson Ph.D., Jonathan Turk Ph.D.,
Saunders College Publishing