Archaeologists have believed to date from 12,000 years ago.
Preserved in an alkaline surface in a shooting range, the footprints come from adults and children walking across mud more than ten millennia ago – and are known as “ghost footprints” because they are .
The 88 human footprints are believed to date from the Pleistocene era, 12,000 years ago, and were found on the Utah Test and Training Range.
“We found so much more than we bargained for,” said Anya Kitterman, Hill Air Force Base’s Cultural Resource Manager.
“These are once-in-a-lifetime discoveries, and I feel blessed to have been able to be a part of them, as well as find ways to bring them to the public,” Kitterman said.
Kitterman is now overseeing a 5,000-acre archaeological survey and a pilot study on the use of non-invasive archaeological techniques, including the use of a magnetometer and ground-penetrating radar, or GPR, while the busy site undergoes annual maintenance and upkeep.
The discovery of prehistoric footprints, at what is now called the Trackway Site, complements the 2016 discovery made nearby at the Wishbone Site.
The sites are within half a mile of each other.
An open hearth, or fire pit, dating to around 12,300 years ago was found at Wishbone, along with burnt bird bones, charcoal and many artefacts such as Haskett projectile points and stone tools.
Evidence was also found for the earliest known human use of tobacco in the world.
Principal investigator Dr. Daron Duke said the most surprising and telling thing about finding the footprints is the insight it provides into the everyday life of a family group thousands of years ago.
“Based on excavations of multiple footprints, we have found evidence that adults with children aged 5 to 12 left only footprints,” he said.
“People appear to have walked in shallow water, the sand quickly replenished the pressure behind them – much like you might experience on a beach – but underneath the sand was a layer of mud that kept the pressure intact after refilling.”
“Our long-term work on the geochronology of this area suggests that these prints are probably more than 12,000 years old,” he said.
Even with the area now part of an active weapons and training area, Duke said in many ways, this serves as a “reserve” for these archaeological sites.
“The Air Force has been very supportive and accommodating of the Trackway discovery,” he said. “They have a mission to complete, and for years Hill AFB has done this while preserving and protecting the archaeological history.”
“We have also collected the infill of the prints to see if we can find organic materials with radiocarbon dating,” Duke said. “We want to further detail the prints themselves about who made up the group and how they used the area. We’re also talking to Native American tribes about their perspectives on the prints.”
Duke said they were fortunate to have several tribal representatives visit the sites of their early ancestors.
“There’s an immediate human connection to seeing human footprints,” he said. “Seeing them from the distant past, especially so much different than it looks today, can have an effect. They were very happy to see this and it was personally rewarding for me to be able to show it to them. We will continue to talk to them about it.”
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