Scientist digging in to boneyard secrets
John Foster wants to get a three-dimensional glimpse at the Mygatt-Moore dinosaur quarry.
A $25,000 grant from the Bureau of Land Management could give him just such a look at the Jurassic burial pit in Rabbit Valley.
The quarry, which has yielded plenty of paleontological secrets, remains a cipher to Foster, paleontology curator of the Museum of Western Colorado, which operates the quarry under license from the Bureau of Land Management.
The quarry contains large numbers of bones of meat-eating allosaurs and their meals, apatosaurs, but Mygatt-Moore was more than a dinosaur fast-food cafeteria, Foster said.
“We have lots of carnivore teeth and chewed bone, but we don’t know exactly why,” Foster said.
One of the confusing elements to the tale of the quarry is the presence of those bones, as well as other bones that show evidence of being tumbled downstream, perhaps for miles, before being buried in the mud with the recently munched bones.
There also are bones that evidently were snapped by the heavy feet of living dinosaurs passing through what was a boneyard.“There were lots of things getting trampled” there, Foster said.
Then there are the pebbles, tiny, dark, rounded-edge rocks, that “are nothing like” the surrounding Morrison Formation sandstone, which holds the fossils some 120 million years old.
The bones of Mygatt-Moore tell much of the story, but not all, Foster said.
With the grant, he wants to take rocks from the quarry, slice them thin and polish them for careful microscopic examination.
The cross-section can offer little clues about how it was that so many bones came to be buried in the same location, Foster said.
In addition, Foster wants to drill around the quarry to define the boundaries of the area in which fossils were deposited, much as miners might drill to define an ore body.
Another technique will be to take a large sample of the earth, about a cubic meter, and break it down to its various constituents, bones, plant material, mud that became rock, and other ingredients that might shed light on life, death and mealtime at what now is the Mygatt-Moore quarry. “We’re breaking new ground, in more than one way,” said Mike Perry, executive director of the Museum of Western Colorado. “We’re looking at this in a whole new light.”
The Mygatt-Moore quarry was discovered in 1981, and the museum has worked it actively since 1986.
The three-year grant was given to the museum as part of the BLM’s effort to encourage scientific understanding of the National Landscape Conservation System, said Kate Stevens, manager of the McInnis Canyons National Conservation Area.