OSL DATING OF INCREASED SAND BLOW ACTIVITY IN THE ORKNEY ISLANDS, SCOTLAND: A RESULT OF VOLCANIC ERUPTIONS IN ICELAND?

OSL dating has successfully dated periods of wind blown sand activity at archaeological sites in the Orkney Islands, Scotland which conform to periods of Holocene climate deterioration elsewhere. A site at Tofts Ness, Sanday was settled from the Neolithic but was abandoned in the late Neolithic/early Bronze Age for approximately 1000 years before being resettled in the late Bronze Age and then permanently abandoned in the Iron Age. Sand layers lying above the late Neolithic soils have been dated by OSL to about 4000 BP and this correlates well with increased sand blow activity and abandonment of the World Heritage site of Skara Brae, also in the Orkney Islands. OSL dating of wind blown sands near to Tofts Ness at Lopness, suggests that sand dunes developed about 3000 BP, this age constrained by midden deposits and a Bronze Age burial underneath.

The climate impact of the Icelandic volcanic eruptions of Hekla 4 and 3 has been reported from archaeological sites elsewhere in Scotland and is thought to have resulted in the abandonment of settlements. We suggest that the dating of climate deterioration and increase in dune-building activity in Orkney also correlates well with the Hekla 4 and 3 eruptions, this being the first evidence to link the Icelandic eruptions to events in the Orkney Islands.