This dinosaur track found at a BLM tracksite 15 miles north of Moab may have been created by the Acrocanthosaurus, which was approximately 40 feet long and weighed up to 6.8 tons. Paleontologists aren't sure, as the Acrocanthosaurus has only been found in Oklahoma and Texas so far. This is one of six different dinosaur tracks from the late Cretaceous time-period to be found at the site. 

This is where the dinosaurs once roamed.

On Friday, June 28 the public is invited to watch as paleontologists unearth trackways that have been hidden for millions of years. There will be guided hikes and opportunities to visit with paleontologists at 10 a.m., 1 p.m. and 3 p.m. at Mill Canyon, 15 miles north of Moab off of Hwy 191.

“It’s a pretty big tracksite,” said ReBecca Hunt-Foster, the paleontologist with the Bureau of Land Management’s (BLM) Moab Field Office. “We’ve found tracks in the area of a football field.”

The tracksite is near the Mill Canyon Dinosaur Trail, which has several dinosaur bones preserved in the rock along a self-guided interpretive walk.

“They’re closer to Hwy 191 than the dinosaur trail. They are about a half-mile from 191,” Hunt-Foster said.

Most of the site is covered with top soil.

“We’re only removing the surface dirt. We’re not removing any tracks from the site,” Hunt-Foster said.

Paleontologists and volunteers from the Moab Chapter of the Friends of Paleontology will be working at the site for about 10 days with wisk brooms and dust pans.

“It is like sweeping a dirt floor,” Hunt-Foster said. “In some places it is only a few inches deep. In some places it is over a foot or three feet deep.”

They plan to clear off the main track surface, then move from there to see which direction the tracks are going.

Dr. Martin Lockley, a paleontologist who has studied many of the dinosaur tracksites in southeastern Utah and western Colorado since the 1980s, has known about the site for years. He is the founder and director of the Dinosaur Trackers Research Group. He has documented the extensive dinosaur trackways from the Jurassic time period found in the Morrison Formation on the western border of Arches National Park.

He will be joined by Polish paleontologist Dr. Gerard Gierlinski, as well as scientists from Korea. Hunt-Foster said that they will be able to learn quite a bit about a variety of dinosaurs that lived in the area during the Cretaceous time period, about 145 to 160 million years ago.

“It’s one of the only trackways in America that is this particular age,” Hunt-Foster said.

The tracks are in the Ruby Ranch member of the Cedar Mountain Formation, that is known for its maroon mudstones that developed in a flood plain.

They’ve found six distinct track ways so far, that may have been set within hours or a few days in the damp mudflat near streambeds.

“There’s one that is a large meat-eating dinosaur similar to a Acrocanthosaurus. It’s between the size of a Tyrannosaurus Rex and an Allosaurus,” Hunt-Foster said. “They’ve only been found in Texas and Oklahoma so far. We may find one here in the Moab-area, but there is more work to be done.”

The print is large, nearly double the length of an average man’s foot.

There are sauropod tracks, the long-necked plant eating dinosaurs. There are tridactyl prints, that come from smaller three-toed meat eating tracks.

“The tracks are a little smaller than human’s foot,” Hunt-Foster said. “It was probably the size of the average human, about five or six feet tall.”

There’s the Ornithopod, which is a birdlike dinosaur; and the Ankylosaur that has armor on their back.

And there’s the Dromaeosaur, which is kind of like the Utahraptor, the intelligent and vicious dinosaurs portrayed in the movie Jurassic Park.

“You get a good variety of tracks preserved at the site,” Hunt-Foster said. “That’s one of the things that makes it so unique.”

Hunt-Foster stresses that it is important to leave the tracks in place to be able to learn more about the animals.

“You can measure the difference between the tracks to determine how tall the dinosaur is. You can also tell how fast they are moving,” she said. “That’s why we don’t like it when people remove tracks from a series or trackway, because we can lose some valuable information when they do that.”

The dirt that is being removed from the tracksite will be used to build trails for a future interpretive site.

“The science is the most important part. There is a trail planned there in the future, but first we need to collect as much data as we can,” Hunt-Foster said.

She wants to remind the public that there is federal law prohibiting the removal of tracks or pouring plaster into the tracks.

“It is prosecutable,” she said. “Time could be served and fines imposed.”

One act of vandalism has already occurred at the site.

“We don’t want it to happen again,” she said. “The public is the eyes and ears to police these sites. If you see anyone pouring anything into the tracks, or removing the tracks, please call the BLM or authorities as quickly as you can.”

Hikers are encouraged to be at the site a few minutes before the tours are scheduled to begin. The hikes are short, but extreme summer temperatures are expected, and hikers should plan accordingly and bring their own water and sunscreen.

Once hikers are in the area, they’re encouraged to see the Mill Canyon Dinosaur Trail that has the preserved remains of Jurassic plant-eating dinosaurs such as the Allosaurus, Stegosaurus, Camarasaurus and Camptosaurus. The fossils reside in the Morrison Formation, from approximately 150 million years ago when the area was wet with shallow lakes and slow moving streams.

What: Dinosaur Trackway Hike

When: Hikes at 10 a.m., 1 p.m. and 3 p.m., Friday, June 28

Where: Mill Canyon, 15 miles north of Moab

For more information please contact the BLM-Utah Moab Field Office at (435)259-2100.


From Moab take Highway 191 north for15miles to Mill Canyon Rd. Turn left onto Mill Canyon Road. and travel approximately one mile to the “Y” intersection of Mill Canyon Road. and Cotter Mine Road. Turn left onto Cotter Mine Road and continue for another half-mile to a second parking area.

Utah Friends of Paleontology, Southeast Chapter

What: Dr. Martin Lockley, will give a talk about his 30 years of tracking dinosaurs in the Moab area.

When: 6:30 p.m., Wednesday, June 26

Where: Grand County Public Library, 257 E. Center St.

It’s a pretty big tracksite. We’ve found tracks in the area of a football field.”