Friday, December 18, 2009

Archaeologists Preserve Underwater Heritage

By Christen N. McCluney
Special to American Forces Press Service

Dec. 18, 2009 - Archaeologists with the U.S. Navy History and Heritage Command are conducting underwater research to study wrecks, recover artifacts and preserve Navy history. "A large percentage of the Navy's history resides in sunken shipwrecks and aircraft ... literally scattered around the globe," Robert Neyland, head of the underwater archaeology branch at the command, explained during a Dec. 16 interview on the Pentagon Channel podcast "Armed with Science: Research and Applications for the Modern Military."

He was joined by Alexis Catsambis and George Schwarz, who also are archaeologists at the branch.

The underwater archaeology branch is responsible for interpreting and applying science and archaeology on the Navy's sunken ship and aircraft wrecks. The team is responsible for the management and study of more than 3,000 shipwrecks from the Continental Navy period to present time and more than 14,000 lost aircraft from the 1920s to the beginning of the Cold War, Neyland said.

The archaeologists also contribute to the understanding of the Navy's and the nation's underwater cultural heritage. They travel all over the world to locate, assess and preserve wrecks that are property of the U.S. government, whether in U.S., international or foreign waters.

The science and technology used to locate and study shipwrecks include diving equipment and remote sensing equipment such as sonar, multi-beams and magnetometers, Neyland said. These tools, which date back to the Cold War, are aided by global positioning devices to locate and survey wrecks.

Catsambis said that because underwater archaeology has evolved only since World War II with the creation of the aqualung, the archaeologists have had an opportunity to draw from larger fields to create a "toolbox of resources" mixing marine sciences, anthropology and archaeology.

"Technology [has] advanced in underwater archaeology on the diving side," Neyland said. "People can go deeper and can stay down longer using mixed gas and rebreathers, going to depths they couldn't go to 20 to 30 years ago."

An example of this is CSS Alabama, a vessel that went down off of the coast of France in 1864. The wreck was in an area with a strong current that allowed divers to explore only in short windows twice a day. Using sonar imagery and divers, the wreck site was explored under the direction of a joint French-American scientific committee.

"What in the past limited diving is now accessible," Neyland said.

Preservation and conservation also play an important role in naval archaeology. "Conserving is treating an artifact and keeping it in a stable condition," Schwarz said. "The long-term care is preservation and keeping them in environmentally controlled environments so they won't be destroyed."

A goal of the underwater archaeology branch is to treat and stabilize artifacts for study and display. Objects such as metals can corrode quickly, leather and other goods can deteriorate, and wood can shrink when recovered from an underwater environment. The branch also works in the investigation of ship and aircraft wrecks to find the remains of servicemembers as well. "One of the really remarkable things archaeology can do is give these unknown sailors a face once again and a history," Neyland said.

"Underwater archaeology really has been interfaced between history and science," he added. "It's a place that brings the historical questions together with the scientific techniques and procedures."

(Christen N. McCluney works in the Defense Media Activity's emerging media directorate.)

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