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Meet the keepers of the Jurassic dead

June 30 , 2016

By Brian Switek

Bracing himself against the Jurassic sandstone, high above the floor of Dinosaur National Monument’s bone-packed quarry wall, paleontologist Dan Chure recalls some of the original plans for the ancient graveyard.

In the initial phases of planning the living museum — when no one was certain how many bones might be uncovered in the tilted rock face — someone had the idea of removing all the bones, reassembling them, and then cementing them back into the stone as panel mounts. Thankfully, this idea was abandoned. So was a suggestion to paint excavated bones with luminescent paint so that visitors could be dazzled with glow-in-the-dark dinosaurs.

Instead, the experts decided to build an enormous frame of steel and glass over the dense, 150-million-year-old bone bed in Colorado. And taking care of this bonanza of a National Park has kept Chure busy for his entire career.

After all, even long-dead dinos need someone to look after them.

[This dinosaur had a heartbreaking life. Now she’s famous — and an inspiration.]

The original building covering the quarry wall was raised from 1957 to 1958. Unfortunately, the engineers that built the place didn’t plan sufficiently for the expanding and contracting shale beneath the building. As experts and volunteers excavated the quarry face, uncovering more than 1,500 bones from dinosaurs such as Allosaurus, Diplodocus, and Stegosaurus, the building started literally ripping itself apart. By 2006, it was in imminent threat of collapsing on itself, Chure says. One of the greatest living exhibits in the world had to be closed.

It took years of work to protect the fossils, remove the old building, and construct a new, more stable edifice that opened to the public in 2011. But even though the museum’s current incarnation has a thoroughly modern feel, with interactive displays and up-to-date dinosaur art, Chure still finds himself managing echoes of the past.

Overseeing a site that’s a bone yard, museum, and exhibit all at once isn’t easy. Chure has to simultaneously think about how to keep the fossils safe – preventing visitors from jumping the gate to crawl on the wall, for starters – but also keep the ancient trove accessible to scientists who want to study the bones. “This is particularly challenging for specimens in areas where access is difficult or impossible” for researchers, such as a neck and beautiful skull of the long-necked dinosaur Camarasaurus that seems to tease from the top of the wall.

Then there are the repairs. “From the galleries,” Chure says, “one can notice a few large cracks but the rock looks solid.” Up close, however, the bone bed is almost constantly changing. Leaning over to the limb bone of a giant that died and was buried around 150 million years ago, Chure points to a jagged crack running through the bone. It was repaired with some unknown adhesive decades ago, but the constant movement of the earth has formed a new break just below it that must now be assessed.

Such fixes only last so long. The sandstone varies in hardness and composition throughout the quarry, Chure says, leading the more friable areas to crack and damage bone more easily.

“Cracks run through bone and sometimes behind them, separating the fossil from the rock,” Chure says, not to mention that “undulating bedding planes may be surfaces along which slippage may occur, resulting in large pieces of the quarry catastrophically failing and sliding to the ground.” No one wants a Camptosaurus-sized chunk of rock to suddenly crash to the floor. Chure has been watching since he took the job in 1979 to make sure this doesn’t happen.

This effort goes beyond clambering over the sandstone itself. Over the years, Chure, park staff, and interns have been looking through historical documents to piece together the living history of the quarry. Past excavation crews used a wide variety of adhesives – from shellac to homemade glues – to stabilize the bones, for example. Finding out what had been used is critical to protecting the fossils, as well as park staff, if some of those old-time fixes have to be undone or repaired.

Records about who used what to patch old bones can sometimes be difficult to uncover. Chure, along with park interns, have been searching the reams of documents that might contain the critical information. Geoscientist-In-Park Nicole Ridgewell is spending her entire summer picking over the quarry face, researching and documenting how to keep the Jurassic fossils together.

Sturdy though they seem, fossils are incredibly fragile. It’s amazing that such delicate remnants of the Jurassic have survived through deep time, not to mention their decades of showing off for scientists and the public alike. They cannot fend for themselves. Even something as solid as a fossil femur still needs a lot of loving care.




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