Exploring the Utility of Bathymetry Maps Derived With Multispectral Satellite Observations in the Field of Underwater Archaeology

Bathymetry maps derived with satellite-based multispectral sensors have been used extensively for environmental and engineering coastal studies and monitoring. However, so far this technique has not been widely exploited in other coastal applications, such as underwater archaeology. Submerged settlements and shipwrecks are often located in water depths where the application of multispectral satellite data is feasible. This could lead to more efficient field work practices thus enabling more optimal allocations of costs and labour during archaeological excavations. This study explores the contribution of processed satellite bathymetry maps to the recording of two archaeological coastal sites: a submerged prehistoric settlement in Greece and a shipwreck of a modern cargo vessel in Italy. The results indicate that even though the accuracy of satellite derived bathymetry is high, the level of detail (spatial resolution) is not sufficient to fully replace field-based measurements. However, the use of satellite data complements the existing techniques and can help to place the archaeological sites within a broader spatial context as well as to efficiently monitor the deterioration of a site due to natural causes or human activity, which inevitably leads to risk management. When the study of larger objects is involved (for example First World War shipwrecks) the potential of using satellite data in underwater archaeological studies becomes more promising.