Separating fact from fiction using ground-penetrating radar
November 12, 2013
Since she began working with ground-penetrating radar (GPR) in 2000, Debbie Surabian has used the instrument to search for all manner of things in the soil, including unmarked graves, buried time capsules, pipes, foundations, water raceways, and even the crash site of a fighter jet.
But finding the objects themselves isn’t what interests the Natural Resources Conservation Service (NRCS) soil scientist the most. It’s learning the truth behind the tales people tell about them. “When I go to these sites, I’m always hearing stories, and they’re part of our history,” Surabian says. “So, is it just a story or is it real?”
One of her favorite examples comes from work she did for a historic cemetery in the Stonington borough of Connecticut. According to the Stonington Historical Society, an English mariner named Captain Thomas Robinson bought 11 acres of land on Long Point in the borough in 1771. He then built a house, sold house lots to others, and began using one lot as a burial place for his family and a few friends. This cemetery was eventually expanded and became known as the Robinson Burying Ground.
The cemetery was thought to contain several unmarked graves, but when Surabian was called in to search for them, she was told about something else that might be underfoot. According to local legend, a British bombshell landed in the cemetery during the Battle of Stonington in 1814 (part of the War of 1812), creating a large crater. When a local woman named Elisabeth Hall died shortly afterward from an illness, her daughter hastily buried her and her bed in the cavity.
“So, I’m thinking, “that’s a great story!’” Surabian says with a laugh, and she decided to make a pass with the radar to look for the crater. During her first run with instrument, she called excitedly to her close collaborator and fellow NRCS soil scientist, Jim Doolittle: “Jim, I think I see it. Wow!”
Upon setting up a search grid to look more systematically for the crater, the pair became even more convinced they’d located it. GPR indicated that the soil used to fill the hole was different from what was there originally. Plus, the soil’s typical structure of horizontal layers, or “horizons,” had been disrupted in what the radar data indicated was a perfect V-shape.
Not surprisingly, the radar failed to detect Elisabeth Hall or her bed; GPR normally doesn’t pick up bones or other human remains, Surabian explains. Still, she’s thrilled to have helped confirm at least part of the story of the unusual burial and the “legend of the crater.”
Sometimes tall tales are true.