“Alaskan Starfish”
Edmontosauraus Hadrosaur humerus

Hell Creek Formation

65 Million years old

Found in Bowman County, ND

End of Cretaceous Period

This mosaic sculpture was created from the field jacket of an Edmontosauraus Hadrosaur humerus found in Bowman County, ND in the Hell Creek Formation.  The Hell Creek Formation is a single sedimentary layer formed approximately 65 million years ago when western North Dakota was a semitropical delta of sediments deposited from rivers originating in the Rocky Mountains.  This represents the end of the Cretaceous period, a period famous for both the appearance of flowering plants and the mass extinction of dinosaurs.  Hell Creek is a particularly interesting formation, for it holds records of this mass extinction.  The Edmontosaurus, one of the largest of the Hadrosaurs, was around 43 ft long and weighed over 4 tons.

 Special thanks to J-P Cavigelli, Tate Geological Museum, Casper College, WY