Page 120 - Manual for Activities directed at the Underwater Cultural Heritage

 © Wessex Archaeology. A sidescan sonar image of a metal wreck lying off the south coast, United Kingdom.
On this image, two masts can be seen extending from the ship. The side-scan sonar imagery allows detailed planning for higher resolution ground-truthing surveys, which can involve the collection of physical samples from the seabed or underwater video.These surveys are usually carried out by a Remote Operated Vehicle (ROV) or submersible, capable of operating in very deep water.
With this range of methods, informed predictions can be made. Unfortunately, the current limitations of geophysics as applied to underwater archaeology mean that a negative result from this method of prospection does not necessarily rule out the presence of archaeological sites in the area prospected. In addition, the archaeologist will always need to carry out soundings. Moreover, the depth of sedimentation needs to be assessed for its potential of containing archaeological traces.
The preparation of underwater archaeological surveys is a basic management tool and needs to be a priority objective of the authorities responsible for conserving the underwater cultural heritage. If it is to be successful, the underwater archaeological survey must conclude by specifying the location of the artefacts, their state of conservation, their scientific interest, the risk of alteration and the corrective measures envisaged. See also under Chapter III.
Investigation and analysis
With proper scientific and technical training, the archaeologist will be able to use the minimum of technical resources needed to obtain the best possible scientific results at the lowest cost and with a methodology that is simple to execute. Essential stages of investigation and analysis, planned in
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Objective, methodology and techniques