October 6, 2016:

by Rose Egelhoff

A team led by the Museum of Moab and the Natural History Museum of Utah recently wrapped up its third year excavating the oldest sauropod in North America at a site located in northern San Juan County. After an eight-day excavation that ended Sept. 10, specimens were transported to the Utah Natural History Museum in Salt Lake City for analysis.

The sauropod, Dystrophaeus viaemalae, was first discovered in 1859 by John Newberry during a military survey. Found in the Morrison Formation of sandstone, Dystrophaeus lived during the late Jurassic period. The Dystrophaeus Project team used radiometric dating to determine that the dinosaur is approximately 158 million years old, making it 4 to 6 million years older than other known sauropods found in the Morrison Formation according to the project’s principle investigator, John Foster, director of the Museum of Moab.

The eight-person excavation team included employees and volunteers for the Museum of Moab and the Utah Natural History Museum and Bureau of Land Management (BLM) interns. Foster and Randy Irmis, curator of paleotology at the Utah Natural History Museum, work together as co-principle Investigators for the Dystrophaeus Project, Foster said.

Dystrophaeus has the potential to fill in gaps in knowledge about sauropods, he said.

“Because it is the geologically oldest sauropod dinosaur in North America, at least as far as skeletons go, we’re hoping it will tell us a little bit about the origin of sauropods here,” Foster said, adding that, “sauropods are the big long-necked, long-tailed guys, like brontosaurus.”

After its discovery, the location of Dystrophaeus was lost for nearly a century until it was rediscovered by a Moab resident in the 1980s, According to Foster. David Gillette, the state paleontologist at the time, was alerted and in 1998 and brought Foster to the site.

Once Gillette stopped working on the project, Foster stepped in. He invited the Utah Natural History Museum to participate in the excavation because at the time, the Museum of Moab did not have the necessary equipment or storage space for specimens, he said.

The recent phase of the excavation started in 2014 when Foster and Irmis received a grant from the Canyonlands Natural History Association. They worked for 12 days in 2014 and a week in 2015.

The work was slow and arduous, Foster said. The site, located approximately 250 feet up on the side of cliff, requires ropes and climbing gear to access. Heavy tools and specimens had to be carried in and out of the site.

This year with funds from National Geographic, the project was able to hire a helicopter to carry materials in and out of the site, he said.

“We got as much done in one week this year as we did in the probably two and a half weeks in the previous two years combined,” due to the helicopter, Foster said, adding that it is too early to know exactly what has been found.

“It’s a little bit of an odd site ... We can’t really see exactly what we’re getting out because there’s a lot of bone and it’s all in sandstone. It’s difficult to dig around it and expose it,” Foster said. “So we’re basically just wrapping up sandstone blocks with bone in them and taking them back to the lab.”

Jessica Uglesich, a BLM intern who worked on the excavation, explained that the Dystropheaus bone was very fragile.

“The sandstone we were digging was actually pretty hard at this site, and because the bone stayed on the surface before it was buried, it was weathered, ” she said. “It was hard to get the sandstone [blocks] out without damaging the bone.”

The team was able to identify a tooth and vertebrae. On the last day of the dig, according to volunteer Brian Switek, “it started to get exciting” when the team overturned several large rocks and found what looked like limb material. Foster said the team also took about 3,000 pounds of bone-filled sandstone blocks from the excavation site.

The bone will be carefully removed from the sandstone back at the Utah Natural History Museum’s laboratory, a process that will take several years, according to Foster.

So far, it looks like the bones belong to one individual sauropod, he said.

“There are no overlapping elements indicating multiple individuals and ... things seem to be coming from different parts of the skeleton,” he said. “So how complete it is, we’re not sure, but it does seem to be one individual comprise of multiple parts.”

Before they know whether the dig will continue, the team has to see if there is enough money, Foster said. On the last day of the dig, workers found material that they were not able to take with them but that hope to retrieve next year.

“We’re still waiting to see exactly how much money we have left, but it’s definitely looking like we’ll be out for at least a week next year with the helicopter,” Foster said.

More information about the Dystropheaus Project is available online at: www.facebook.com/Dystrophaeus/.

http://www.moabtimes.com/view/full_story/27275410/article-Dinosaur-dig-of-oldest-sauropod-in-North-America-uncovers-new-clues?instance=secondary_two_leftcolumn