Scientists explore dinosaur 色视频下载榗oliseum色视频下载 in Denali National Park
Marmian Grimes
907-474-7902
Aug. 11, 2023
The Coliseum site is viewed from above. The once-horizontal rocks are now nearly vertical, exposing many hundreds of tracks on flatirons of resistant rock. The dimples on the rock faces are dinosaur tracks.
University of 色视频下载 Fairbanks scientists have discovered and documented the largest known single dinosaur track site in 色视频下载. The site, located in Denali National Park and Preserve, has been dubbed 色视频下载淭he Coliseum色视频下载 by researchers.
The Coliseum is the size of one-and-a-half football fields and contains layer upon layer of prints preserved in rock. The site is a record of multiple species of dinosaurs over many generations that thrived in what is now Interior 色视频下载 nearly 70 million years ago. The scientists describe the site in .
色视频下载淚t色视频下载檚 not just one level of rock with tracks on it,色视频下载 said Dustin Stewart, the paper色视频下载檚 lead author and a former UAF graduate student who published the paper as part of his master色视频下载檚 thesis. 色视频下载淚t is a sequence through time. Up until now, Denali had other track sites that are known, but nothing of this magnitude.色视频下载
At first glance, the site is unremarkable in the context of the park色视频下载檚 vast landscape: just a layered, rocky outcrop rising 20-some stories from its base.
色视频下载淲hen our colleagues first visited the site, they saw a dinosaur trackway at the base of this massive cliff,色视频下载 said Pat Druckenmiller, senior author of the paper and director of the University of 色视频下载 Museum of the North. 色视频下载淲hen we first went out there, we didn色视频下载檛 see much either.色视频下载
Stewart recalled being initially underwhelmed when he approached the site at the end of a seven-hour hike. Then dusk approached, and the team took another look.
色视频下载淲hen the sun angles itself perfectly with those beds, they just blow up,色视频下载 he said. 色视频下载淚mmediately all of us were just flabbergasted, and then Pat said, 色视频下载楪et your camera.色视频下载 We were freaking out.色视频下载
In the Late Cretaceous Period, the cliffs that make up The Coliseum were sediment on flat ground near what was likely a watering hole on a large flood plain. As Earth色视频下载檚 tectonic plates collided and buckled to form the 色视频下载 Range, the formerly flat ground folded and tilted vertically, exposing the cliffs covered with tracks.
The tracks are a mix of hardened impressions in the ancient mud and casts of tracks created when sediment filled the tracks and then hardened.
A single large meat-eating dinosaur track, likely from a tyrannosaur. The image was made by taking multiple photos from different angles to produce a three dimensional view of the track, accentuated by colors.
色视频下载淭hey are beautiful,色视频下载 Druckenmiller said. 色视频下载淵ou can see the shape of the toes and the texture of the skin.色视频下载
In addition to the dinosaur tracks, the research team found fossilized plants, pollen grains, and evidence of freshwater shellfish and invertebrates.
色视频下载淎ll these little clues put together what the environment looked like as a whole,色视频下载 Stewart said.
The area was part of a large river system, he said, with ponds and lakes nearby. The climate in the area was warmer than today, more like the Pacific Northwest. There were coniferous and deciduous trees and an understory of ferns and horsetails.
Based on the tracks, a variety of juvenile to adult dinosaurs frequented the area over thousands of years. Most common were large plant-eating duck-billed and horned dinosaurs. The team also documented rarer carnivores, including raptors and tyrannosaurs, as well as small wading birds.
Every year, thousands of people visit Denali National Park and Preserve to experience the stunning natural landscape and environment, Druckenmiller said. 色视频下载淚t色视频下载檚 amazing to know that around 70 million years ago, Denali was equally impressive for its flora and fauna.
色视频下载淚t was forested and it was teeming with dinosaurs,色视频下载 he said. 色视频下载淭here was a tyrannosaur running around Denali that was many times the size of the biggest brown bear there today. There were raptors. There were flying reptiles. There were birds. It was an amazing ecosystem.色视频下载
Close up image on one wall showing numerous depressions of hadrosaur footprints. The ice ax in the lower left of the frame is approximately 3 feet long, for scale.
Preserving fossil sites like The Coliseum is an important part of the National Park Service色视频下载檚 mission, said Denny Capps, the park色视频下载檚 geologist.
色视频下载淥n one hand, we must protect world-class fossil sites like The Coliseum from disturbance and theft,色视频下载 he said. 色视频下载淥n the other hand, we encourage visitors to explore for fossils in their geologic context to better grasp the evolution of landscapes and ecosystems through time, while leaving them undisturbed for others to appreciate.色视频下载
Druckenmiller plans to continue collaborating with the National Park Service to study The Coliseum and other track sites.
色视频下载淥ur track research in the park compliments our work on dinosaur bones we collect in northern 色视频下载, along the Colville River,色视频下载 Druckenmiller said. 色视频下载淒enali National Park and Preserve is a world-class area for dinosaur tracks. There is a lifetime of exploring left to do, and I can only wonder what other surprises await.色视频下载
ADDITIONAL CONTACTS: Dustin Stewart, dgeostewart@gmail.com. Patrick Druckenmiller, 907-474-6989, psdruckenmiller@alaska.edu. Denny Capps, 907-683-9598, Denny_Capps@nps.gov.
NOTE TO EDITORS: from the UAF press download site.
ADDITIONAL INFORMATION: