Development of Tools for Surveying and Monitoring Coastal and Underwater Archaeological Sites (WP2)

Mapping and monitoring of an archaeological site is a prerequisite for determining its location, its extent and for assessment of its physical stability. Remote sensing techniques are one of the most cost effective tools for regional scanning of the seabed surface, sediments and their morphology as well as assessing the physical stability of archaeological sites. State of the art satellite imagery techniques are able to monitor changes in coast line morphology and sediment transport in shallow water environments (to depths of 6-8 metres). On underwater sites, sidescan sonar, sub-bottom profilers, magnetometers, and single and multibeam echosounders have been used to locate and map archaeological sites both on and within the seabed. Although the use of these tools is not new to marine archaeology, development of existing technologies is one of the significant impacts of the SASMAP project. By contrast, 3D shallow seismic is a cutting edge method and together with other new technologies developed within the project, will give detailed 3D imagery of archaeological sites and environs.

Following a down-scaling approach, i.e. working from the large regional scale to the detailed site scale, will yield seamless maps that can be used for assessing coastal and submerged archaeological sites. This will be achieved by the following:

  • satellite imagery for case study areas (Denmark and Greece) will be purchased from a satellite image providing company and assimilated into a Geographical Information System (GIS), in order to map the coastline and sediment transport in 3D. The development and use of the GIS will contribute to developing a best practice for large scale assessment of the coastal and foreshore zone.
  • the stability of the case study areas will be investigated through observing the 3D terrain models of the sea bed surface area obtained from multibeam echosounder (MBES) surveys over the case study areas during the project time span. These data will also be assimilated into the GIS and by comparing data sets from the satellite imagery with MBES data, hot spot areas of the sites which are being eroded, due to sediment transport or conversely covered with sediment, will be identified. These areas will be verified (ground truthed) in connection with research undertaken in WPs 3, 4 and 6.
  • A prototype 3D parametric sub bottom profiling system (SBP) will be applied to the area at a local scale in order to obtain a 3D map of the sediment structures and to identify archaeological artefacts within the site. This system has not previously been used in shallow water and will be trialled alongside a proprietary ‘CHIRP’ SBP system, currently considered the best commercially available tool for imaging buried archaeological artefacts. The potential application of this new system to archaeological prospection will thus be assessed. These data will also be assimilated into the GIS. Trialling the prototype system on the site in Greece where the carbonate bedrock is very different to the postglacial and glacial sediments typical of north-west Europe, will evaluate its range of applicability to marine archaeology. A GIS will be developed using state of the art remote sensing techniques and data in order to holistically localise, map and monitor archaeological remains in submerged environments on a large scale.