The Red Gulch Dinosaur Tracksite is the largest tracksite in Wyoming and one of only a few worldwide from the Middle Jurassic Period (160 million to 180 million years old). Until the tracks were reported in 1997, most scientists thought the entire Bighorn Basin and most of Wyoming was covered by an ancient ocean called the Sundance Sea.
Scientists thought that only sea-dwelling creatures could have lived in this area. There shouldn't be any dinosaur footprints at all. Not only are there hundreds of tracks, but in this 40-acre area there could be thousands. The dinosaur tracks were clearly made just at the shoreline, not in deep ocean water, and there must have been large areas of dry land to support not only dinosaurs but other animals and plants.
The limy mud that the dinosaurs were walking in probably felt similar to cement just starting to harden. The tracks were perfectly preserved when the mud hardened and was covered by more layers of ooze, and then by fine sand, filling the tracks and preserving their shape. Over the years, layer upon layer of sediment filled in over the top. Much later, erosion went to work and removed those layers, exposing the tracks that had been made all those millions of years ago.
The tracks were reported in 1997 by Greybull native Erik Kvale while enjoying the scenery with Allen Archer, Rowena Manuel, Cliff Manuel and Fran Paton on BLM-administered lands.