Chris Southerly Wilmington, N.C. Age: 44 Years on Job: 11 |
Essential Equipment
Full Face Mask
"In many cases the waters we're working in have zero visibility," Southerly says. To communicate with fellow divers and the surface crew, he uses scuba gear with a full face mask. Unlike typical scuba equipment, which requires a diver to breathe through a mouthpiece, the mask allows Southerly to talk to other divers up to 150 feet away via a radio link.Portable Magnetometer
After using sonar to identify a site, archaeologists deploy portable magnetometers that detect the presence of iron under layers of sediment to pinpoint the best spots for excavation. "Detecting range is based on distance from the object and the magnetic disturbance it causes," Southerly says. "A cannon might be detectable from 15 feet, while a cannonball may only be detectable from 5 feet."Hammer and Stakes
"Archaeology is a destructive science," Southerly says. "Once we dig it up, we can never put it back the way it was." Without context, artifacts are nearly worthless, so archaeologists document the site meticulously. Using stakes and synthetic decking boards, they create a 5 x 5?foot grid on the seafloor, then map the location of the artifacts on waterproof paper.Sluice
Southerly uses a suction tube to remove small items from the wreck to a sluice, or artificial water channel, on the ship's deck. Sand and mud flow with the water until they are discharged at the end of the sluice, while heavier artifacts, such as nails or shotgun pellets, drop out of the flow into a separate channel, where they're identified and labeled. Larger items are hoisted up with an electric winch after they've been tagged and mapped on the seafloor.tyler bray tyler bray san antonio weather austin box austin box the academy is the academy is
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