College Station -- They say you can't teach an old dog new tricks, but a seasoned archaeologist learned one: computed tomography (CT) scans can be useful tools in both medical and archaeological applications.
The College of Veterinary Medicine and the Institute of Nautical Archaeology at Texas A&M University used a CT scan at the Veterinary Medical Teaching Hospital to interpret historical artifacts from the Denbigh, a British merchant ship used as a blockade-runner during the American Civil War, which sank off the coast of Galveston in 1865.
Researchers with the Denbigh project began recovering artifacts after discovering the wreck in 1997. J. Barto Arnold III, principal investigator with the project, met with Dr. Ian Tizard, a professor in the College of Veterinary Medicine, regarding his expertise in constructing ship models. Tizard began reconstructing the ship from historical documents. When Arnold inquired about the possibility of CT scans prior to artifact cleaning, he suggested that Arnold contact a radiology specialist at the Veterinary Medical Teaching Hospital.
"These are very intricate conglomerates, so we needed more than the radiograph images that we usually use," Arnold said. "The only way we could safely begin chipping these finds apart was by knowing exactly where the pieces were joined and what lay within."
Dr. Michael Walker, a radiologist and professor at the College of Veterinary Medicine, offered an analysis of CT scans from the two artifact conglomerates, held together by corrosion, sand and shell deposits. The CT scan was used to make images of five millimeter thick slices obtained sequentially from each of the artifacts.
"We were not sure this was going to be a successful endeavor because we had no way of knowing what material was inside. High concentrations of metal would have caused the images to lose detail," Walker said, "Luckily, that was not the case."