UO researchers discover the first dinosaur fossil in Oregon

Scientists from the University of Oregon have discovered a rare and extraordinary object: a bone belonging to a terrestrial dinosaur, the very first fossil of a terrestrial prehistoric creature discovered in the state.

The discovery took place in 2015, when Earth Science professor Greg Retallack was in central Oregon, leading a field expedition of students looking for fossilized plants near the city. from Mitchell, in a flagship site of ancient rocks called the Hudspeth Formation.

The group fell on a pile of ammonites, spiral-shaped sea creatures that disappeared at about the same time as the dinosaurs. Retallack said that sitting at the top of the pile was a bone.

"I immediately knew what it was," he said. "The students were a little mystified, but I was delighted."

The revelation of Retallack was first revealed in an article published this month in the Journal of Vertebrate Paleontology.

The fossil, a toe, would be about 103 million years old, dating back to the Cretaceous. It belonged to a creature called ornithopod, a 17-foot-long herbivore weighing up to 1,500 pounds and walking on two legs.

To understand the importance of discovery, you need to know what Oregon looked like over 100 million years ago.

At the time, the Pacific Ocean was spreading far and wide inside the beaches we know today and the coast started at the Blue Mountains in what is now the Pacific Ocean. East of Oregon. The shoreline was rocky and rugged and all that was happening west of Wallowa was submerged.

"The landscapes of Oregon are rich in Cretaceous rocks, but they rarely contain the remains of dinosaurs that we see elsewhere in the United States," said Retallack in a statement. "The rocks here are of good age, but mostly come from the sea where dinosaurs did not live or swamps where dinosaur bones are rarely preserved."