2003 Strategic Environmental Assessment SEA4 Technical report - Archaeology (Continental Shelf Area)

This report is a contribution to the Strategic Environmental Assessment (SEA4) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change) and discusses the potential for prehistoric archaeological remains to exist on the continental shelf part of the SEA4 area. The combination of post-glacial sea level rise and the subsidence of the shelf to the north of the Scottish mainland indicates that a large area of the present shelf, out to a water depth of about 150m on either side of the Orkney-Shetland Ridge, may have been dry land over 5000 years ago. Submarine archaeological studies in the Danish archipelago have established that coastal sites were an optimal place for prehistoric occupation. There is a great density of prehistoric sites in the Orkney and Shetland archipelagos, dating back to as early as 6000 years BP. Submerged sites could date back to about 9000 years BP. While shelf sites exposed to strong currents and Atlantic storm conditions are unlikely to have survived, the survival of more protected sites is quite likely. Locations where prehistoric remains might occur and have a high chance of survival are discussed. The potential impact of oil and gas operations on submarine archaeological remains is discussed. Pipe entrenching is the most likely process to uncover prehistoric archaeological deposits.