May 2001

From University of North Carolina at Chapel Hill

UNC work on Blackbeard wreck offers chance to develop techniques, reveal state, nation's past

CHAPEL HILL - Raising one of Blackbeard's largest crusty cannons, as divers plan to do off Atlantic Beach, N.C., Wednesday (May 9), is among the more visible and exciting aspects of salvaging a pirate wreck that's lain submerged 20 feet below the surface for nearly three centuries. The cannon, dubbed "Baby Ruth 2," will be the largest artifact yet retrieved from its sandy grave.

Much detailed science is involved, researchers say, along with an almost unprecedented level of teamwork among North Carolina marine experts and others.

"The 'Queen Anne's Revenge' project is one of the best examples I have seen in my 16 years at the University of North Carolina at Chapel Hill in which marine sciences faculty members have stepped forward to provide research expertise to aid in preservation of cultural resources," said Dr. John Wells, director of the Institute of Marine Sciences. "The wreck site is of immeasurable cultural and historic value to the people of North Carolina."

Mark Wilde-Ramsing, director of the recovery project agreed, and said the institute in Morehead City had been instrumental in keeping the effort going.

"Not much more than a year ago, the project had no research facility to analyze and conserve the thousands of artifacts that had been recovered during initial testing and emergency recovery expeditions," Wilde-Ramsing said. "The future looked bleak until UNC-Chapel Hill's Institute of Marine Sciences provided space.

"Now we have the capability to conduct the highest level of study and conservation on these remarkable artifacts," he said. "The public often thinks exploration of shipwrecks is a goody hunt. The truth is archaeology requires painstaking research to reveal what was really going on at the time of its wrecking. Here at the institute we are surrounded by a variety of scientists studying the marine environment who can help the project archaeologists learn about this fascinating period of history." One key question UNC-Chapel Hill researchers are concentrating on involves using sophisticated survey instruments to investigate storm-related changes on the seafloor where the artifacts are vulnerable, Wells said.

Wells works with Dr. Jesse McNinch, visiting research assistant professor at UNC-Chapel Hill and assistant professor of physical sciences at the Virginia Institute of Marine Science. "Blackbeard's misfortune has given us an incredible opportunity to understand the processes controlling the fate of artifacts in the marine environment," McNinch said. "We are using a suite of instruments -- real-time kinematic global positioning system, electromagnetic current meters, interferometric swath bathymetry and side scan sonar to repetitively map the wreck site and measure currents around the artifacts."

High-resolution maps resolve subtle changes in the seabed, on the order of two inches and show dramatic seafloor scour around the artifacts during storms, McNinch said. They also allow study of long quiet conditions and burial by sediment settling from the water column.

"This information serves as a cornerstone for a conceptual model we are developing that will help predict the location and long-term fate of cultural resources in shallow coastal waters," he said. Besides his other research in coastal North Carolina and tropical rain forests of Brazil, Dr. Christopher S. Martens, William B. Aycock professor at UNC-Chapel Hill, also has been closely involved in researching the pirate ship.

"The first analyses we did involved radiocarbon dating wood and various organic samples from the ship, and that's continuing," Martens said. "The second was plutonium work to see if there had been any disturbance of the hull. We found very little plutonium fallout that came from atmospheric atomic weapons testing beginning in the 1950s under the hull. That showed sediments were not exposed much, and hence the ship had not moved much, at least since the 1950s."

Wood from anchor stocks, planking, ribbing, caulking and pegs that held the ship together will continue to be analyzed at the National Ocean Sciences Accelerator Mass Spectrometry facility at Woods Hole Oceanographic Institution on Cape Cod. Those analyses, including studies of sequential tree rings in the largest wood planks, should help show how old trees used to build major parts of the ship were. So far, he said, researchers believe the trees used by shipwrights to build the QAR grew between about 1620 and 1700.

"Baby Ruth," raised in October 1999, turned out to be two smaller loaded cannons, Wilde-Ramsing said. To date, divers have brought up five big guns for conservation, and 17 others have been identified. The wreck, located in 1996 by Maritime Research Institute and Intersal Inc. divers, might hold as many as 40 such weapons.

Organizations involved in the recovery and conservation include the N.C. Underwater Archaeology Branch, N.C. Department of Cultural Resources, UNC-Chapel Hill, UNC-Wilmington, East Carolina and Appalachian State universities, N.C. Marine Fisheries, Carteret Community College, the N.C. Maritime Museum and others, Wilde-Ramsing said. Public response to educational programs about "Queen Anne's Revenge" has been almost overwhelming.

By DAVID WILLIAMSON
UNC News Services

Note: Wilde-Ramsing and Wells can be reached at 252-726-6841. Martens' number is 919-962-0152. McNinch can be reached at 804-684-7191












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