​Thornton Dinosaur - 66 Million Years in the Waiting

Rare dinosaur fossil uncovered in Thornton

Dinosaur Discover Timeline:

  • Monday, July 31: The city of Thornton breaks ground on new Fire and Police Substation, 132nd Avenue and Quebec Street.
  • Friday, August 25: Crews moving ground with a skid-steer loader are stopped by an ‘immovable’ object. One crew member realizes it might be a fossil, and work in that area is stopped. The Denver Museum of Nature and Science is contacted.
  • Monday, August 28: DMNS Curator of Dinosaurs Joe Sertich visits site, and recognizes find as a dinosaur fossil, specifically, part of a skull from a triceratops.

Media Resources

Video Files:

09/18/2017 Video Files

09/08/2017 Video Files

09/07/2017 Video Files

09/06/2017 Video Files

09/05/2017 Video Files

09/01/2017 Video Files

08/31/2017 Video Files

08/30/2017 Video Files

08/28/2017 Video Files


Click here for photo files.

Curator of Dinosaurs, Denver Museum of Nature and Science
Interview date: August 28, 2017

00:37  As soon as I got onsite, I realized it was a pretty important dinosaur find, which are pretty unusual in the Denver area.

00:45 After cleaning up the site, it looks like part of a skull of a triceratops, the horned dinosaur, and maybe part of a skeleton.

00:54 Dinosaurs from the Denver area have been known for about 150 years, but most of Denver is covered by parking lots or houses, shopping malls, and so it’s pretty unusual to get down to the original rock layers that Denver sits on. And so whenever a construction site like this gets down to the right level, like it did here in Thornton, rocks that pre-date the extinction of dinosaurs, right before the dinosaurs go extinct, you have things like T-Rex and triceratops walking around the landscape, and so this construction site hit the right spot at the right time.

01:40 What’s really unusual is getting some of these sites reported. So, a lot of times these will be plowed up and they won’t be recognized. And we’re really lucky in this case that it was recognized as fossils and we got the call and were out here and able to salvage the site, and actually collect these fossils.

01:59 This is probably one of only three skulls of triceratops found along the front range area.

02:05 The triceratops is that iconic really popular dinosaur, most kids know it. Its got the two horns, big horns over its eyes, and a little nose, nose horn, and then a beak on the front, and a big frill or shield on the back of the head. It’s one of the iconic ones you see fighting T-Rex in the dinosaur horror movies.

02:27 So, the next steps, we’ve got the site figured out. We know there are a lot of bones. There are bones from the skull, bones from the rest of the skeleton, which means it could be a pretty large area to encompass most of the skeleton. And so, the next steps will be to come out and expose more, but also to stabilize and collect what has already been uncovered and get that safely out of the ground.

02:55 This dinosaurs been laying here for at least 66-million years and we’re going to get it out of the ground and get it cleaned up and hopefully house it at the Denver Museum in a nice shiny new cabinet.

03:15 We get a lot of calls about fossils in the Denver area, this past year, we got a tusk from Cherry Creek, so those do come out of the ground regularly and they usually happen to be Ice Age fossils like mammoths, camels, things like that.

03:31 So, when I first got a call about bones, I thought that’s what it was, another Ice Age site. Mainly because this area was covered with Ice Age animals just 10 or 12-thousand years ago.

03:43 The fact that we’re deep enough that we’ve hit the old rock in this area means that it’s dinosaurs. That’s really unusual, really exciting.

03:48 I’m over the moon right now that this is a dinosaur fossil.

03:55 When you first realized it was a dinosaur: My heart was racing! As soon as uncovered it and realized this was a horn of a triceratops and not just another leg bone or part of a hip, it made the site really exciting.