18TH AND 19TH CENTURY COASTAL SAND INUNDATION, SHETLAND UK

Coastal sand invasions in northern Europe are identified from prehistoric archaeological sites, and are recorded in historic documents as early as the 9^th Century to the late 19^th Century. The most recent extensive sand mobilization in this area is often associated with the Little Ice Age. These large-scale movements of sand caused widespread property damage, and rendered large tracts of land unsuitable for agriculture. The study site, the Township of Broo in Quendale Links of the Shetland Isles, UK, was inundated by sand during the 17^th and 18^th centuries. Archaeological excavations at Broo, approximately 2 km from the coast, have exposed a 17^th century farmstead that was covered by up to a meter of wind-blown sand, forcing abandonment of what had been one of the most productive areas on the island. Ground Penetrating Radar (GPR) was employed as a prospection tool, in conjunction with excavation and OSL dating, to identify archeological structures and to determine if the 17^th century event was an isolated occurrence or the last in a series of sand invasions. Investigations using 500MHz GPR indicates an additional buried structure adjacent to the excavated site, measuring at least 20m*5m. Nearby coastal dune faces were excavated and sampled in a previously disturbed sand mine to minimize disturbance and to reach portions of the dune that were otherwise inaccessible. Barbed wire was found 2.12m below the surface on the backside of the foredune during one of the excavations. If this fencing dates to the earliest known use of barbed wire in the region, there has been at least 2.12m of sand accumulation in the past 150 years. Results show that the 17^th century event was not an isolated occurrence, but one of several sand invasions that occurred as early as 3700 BP, and that sand has continued to accumulate within the past 150 years following drastic sand movement in earlier centuries.