This undated handout photo provided by the National Geographic Society shows a technician at the Black Hills Institute of Geological Research in South Dakota working to prepare the fossil of the mummified dinosaur. One of the most complete dinosaur mummies ever found is revealing secrets locked away for millions of years, bringing researchers as close as they will ever get to touching a live dinosaur. (AP Photo/Phillip Manning, National Geographic Society)
Salt Lake City (AP) - Researchers at Dinosaur National Monument had to use explosives to break through layers of rock-hard sandstone to continue excavating an important fossil site.
The quarry - known only as DNM 16 - years ago yielded a complete and intact Sauropod skull, one of the rarest finds among dinosaur diggers.
But as the excavation went on, researchers found they were unable to get through the thick rock to extract remaining bones at the quarry. Most of the work shut down in 2007.
Crews from Rocky Mountain National Park came to the monument earlier this month and blasted the site over three days.
The lead paleontologist at the monument says the unusual step to use explosives has cleared the way for researchers to return this spring.
The monument straddles the Utah-Colorado border.
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