Scanning Sonar System for Submerged Archaeological Sites
Lake Champlain Maritime Museum (LCMM) continues to undertake innovative research in the non-invasive documentation of submerged archaeological sites. Scanning sonar units are now capable of capturing three-dimensional scans of complex underwater objects. This technology has the potential to greatly enhance the study of submerged archaeological sites located in turbid waters where detailed archaeological documentation is impractical. Funding from the National Park Service’s National Center for Preservation Technology and Training allowed LCMM to pursue this research, utilizing scanning sonar equipment from Teledyne BlueView.
The Teledyne BlueView BV 5000-2250 is a tripod-mounted device that takes millions of individual sonar readings and displays the results as a three-dimensional (3D) point cloud. LCMM used this technology to make a detailed examination of the Sloop Island Canal Boat which sank in Charlotte, Vermont during the first quarter of the twentieth century.
Using equipment supplied by Teledyne BlueView, LCMM archaeologists deployed a BV5000-2250 3D Mechanical Scanning Sonar to more than forty locations around, on, and within, the wreck site. At each of these positions the sonar was able to capture accurate 3D images of the shipwreck, which were then assembled into a detailed 3D model of the entire wreck. This composite image, consisting of 35 million data points, allows the remains of the Sloop Island Canal Boat to be examined in a completely innovative way.
Detailed archaeological drawings of the shipwreck site were originally created by LCMM archaeologists after more than 300 dives in 2002 and 2003, employing traditional manual documentation techniques. In contrast, data gathering with the new technology in 2012 took only three days. This new technology offers the ability to efficiently record submerged cultural resources in great detail in only a fraction of the time it would take for archaeologists to document them using traditional recording techniques of measuring and drawing.
Maritime Museum archaeologists will continue post-processing the newly captured data and making comparisons with their original findings.
If proven accurate, this new technology offers the ability to quickly record submerged cultural resources in great detail in only a fraction of the time it would take for archaeologists to document them using traditional recording techniques. The Museum plans to exhibit images captured by this technology in the Nautical Archaeology Center during the 2013 season. The Museum will also produce a manual outlining best practices for the use of this technology by other archaeologists in the spring of 2013.
BlueView's BV5000 3D mechanical scanning sonar is capable of creating high-resolution imagery of underwater areas, structures, and objects by creating a 3D point cloud of an underwater scene. The BV5000 can be deployed from a tripod set on the bottom leading to laser-like scanning capabilities underwater. The point cloud consists of millions of individual measurements which as a group create a three-dimensional image of the underwater subject. The BV5000 has been used with great success in the oil and gas industry, but has only been used for one archaeological project, the study of the steamboat A.J. Goddard sunk in 1901 in LaBerge Lake in the Canadian Yukon (more about Goddard's history). This use allowed researchers to take measurements, cross-sectional views and create 3D visualizations and virtual flights around and inside the wreck (more about the use of BlueView on Goddard).