North Dakota Stratigraphy Edmontosaurus ROCK ROCK UNIT COLUMN Common Name: PERIOD EPOCH AGES MILLIONS OF YEARS AGO Holocene Oahe .01 Duckbilled dinosaur
Coleharbor Classification: Pleistocene QUATERNARY 1.8 Pliocene Unnamed Class: Reptilia 5 Miocene Order: Ornithischia 25 Arikaree Family: Hadrosauridae
Brule Lower jaw of the duckbilled dinosaur, Edmontosaurus. Collected Oligocene
38 and donated by Tyler Lyson, Marmarth. Cretaceous Hell Creek South Heart Chadron Chalky Buttes Formation. Slope County. 460 mm wide. North Dakota State
Camels Butte Eocene Golden Fossil Collection. 55 Valley Bear Den Description: Sentinel Edmontosaurus was the most common duckbilled dinosaur Butte
TERTIARY hadrosaur) that lived in North Dakota during the Cretaceous. The front of the face of hadrosuars was elongated into a broad, flattened snout with a toothless beak. This beak looked rather like
Bullion the bill of a modern duck, hence the popular name “duckbilled Paleocene Creek dinosaur.” Edmontosaurus was a large, plant-eating animal that grew to lengths of 40 feet. It is one of the best known dinosaurs Slope because many fossils of this species have been found and studied.
Cannonball They had large pillar-like legs, powerful ankles, and bony tendons in their backbone which helped support the animal as it walked on Ludlow 65 land. Each foot possessed three broad, widely spaced toes ending Hell Creek in hooflike nails. Unlike many duckbilled dinosaurs, Edmontosaurus did not have a crest on its skull. It did have Fox Hills strong lower jaws that contained batteries of hundreds of small teeth that formed grinding surfaces for eating coarse vegetation. These teeth acted like a rasping file and could pulverize tough plant
ACEOUS Pierre food such as conifer needles, twigs, and cones. There were no
CRET teeth in the front of the mouth. Worn teeth were continually replaced by new ones throughout the life of the animal. 84 Edmontosaurus skin impressions have been found indicating that Niobrara it had a thin, leathery hide studded with horny tubercles. Many Carlile hadrosaurs lived in large herds and some may have cared for their young at nesting sites. Fossil evidence indicates that Carbonate Calcareous Shale Claystone/Shale Tyrannosaurus rex preyed on the duckbilled dinosaurs. Siltstone Sandstone Sand & Gravel
Mudstone Lignite Glacial Drift
Edmontosaurus. Painting courtesy of Simon and Schuster Publishing Company. Locations where fossils have been found ND State Fossil Collection Prehistoric Life of ND Map North Dakota Geological Survey Home Page