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Ogden dinosaur park unveils large hadrosaur fossils

OGDEN — Seventy-five million years ago, give or take half a million years, something bad happened to a large hadrosaur.

Scientists can only guess what brought the plant-eating beast, which is the size of a Tyrannosaurus rex, into a flood channel where it was buried in sediment that later became sandstone, preserving the fossilized bones and even some skin impressions.

In a 75-by-15-foot excavation site at Grand Staircase-Escalante National Monument, paleontologists in 2007 also unearthed the fossils of three turtles, a crocodile, an armored ankylosaurus and a pterosaur.

How the ancient animals ended up together may be a mystery, but where the fossils are going isn't.

On Thursday, the George S. Eccles Dinosaur Park received various plaster-soaked wrappings, known as field jackets, with the hadrosaur fossils inside.

Volunteers at the dinosaur park will spend the next few months preparing the fossils, which later will be assembled at the new Utah Museum of Natural History, which is under construction near the University of Utah.

The fossils are encased in rock, which must be carefully removed. Then, bones will be cleaned and catalogued and sent to the museum.

The dinosaur, which belongs to the genus Gryposaurus, is a large herbivore similar to various duck-billed dinosaurs.

Just its toe bone is larger than an average human foot.

Work to get the fossils excavated enough for transport took nearly two years, said Alan Titus, paleontologist for Grand Staircase.

Titus has seen most of the dinosaur work at Grand Staircase over the past 10 years. During that time, 80,000 of the monument's 1 million acres have been surveyed.

Titus said 3,500 new vertebrate fossil sites have been opened, though most yield small fragments, such as teeth or bones.

It's just a small fraction of sites that hold a dinosaur that's 80 percent complete.

Mike Getty, collections manager of paleontology at the Utah Museum of Natural History, said the hadrosaur was discovered at a lucky time — just as rock around it was starting to erode.

Once sections are excavated, they are wrapped in paper towels and then covered in plaster-soaked burlap, which Getty and volunteers began opening Thursday to reveal bones and impressions of scales in the stone.

The hadrosaur's bones will be prepared by August, and visitors to the dinosaur park can watch over the next few months as trained volunteers clean and remove bone from rock.

Kevin Ireland, the dinosaur park's manager, said when the park was built 15 years ago, it was designed to be a place where people could see and learn how dinosaur bones are preserved.

The park's lab is equipped with windows so visitors can look in on progress, ask questions and even touch an occasional dinosaur bone.

"Everything we do here is educational-based," Ireland said. "Mike (Getty) keeps us busy."

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