EHG5623 - Geophysical surveys - Staffin Bay, Skye

Geophysical surveys were undertaken by UHI Archaeology Institute in 2015 to investigate a suspected Mesolithic site above the raised beach at the eastern end of Staffin Bay. Rthree techniques had been intenced to be used, magnetometry, earthg resistance (resistivity) and ground pemetrating radar (GPR). In the event magnetometry was not used as it was not possible to zero the m gnetometer instrument correctly due to highly magnetic bedrock in the area. It would not have been possible to collect data exposing the small differences in response that is typical from archaeological deposits, as the responses from the bedrock would have been overbearing. The magnetometer survey was therefore abandoned and no data was collected. For the resistance survey different sampling intervals were used. The northern part of the survey was surveyed with a sampling interval of 50cm x50cm to obtain a very fine resolution across the site. The survey was then extended to the south where a sampling interval of 100cm x 50cm was adopted providing a good compromise between resolution and time available. The GPR survey was carried out at the northern end of the project area over what appeard to be a samll structure. Both techniques produced meaningful results and confirmed the features visible on the ground surface and also provided evidence for the complexity of the structure. The results of these techniques generally corresponded with the results of the subsequent excavation (see EHG5624). Significantly, the results of both the earth resistance and GPR suggest that the two sections of bank / walling at the site, which apparent form part of the same structure, are likely to represent different phases of construction and may not have formed a cohesive structure or enclosure. The geophysics, however, did little to characterise the underlying Mesolithic horizon. <1>