Estimating the age of stone structures using OSL:: the potential of entrapped sediment

We report on the potential of using optically stimulated luminescence (OSL) to determine the construction age of various stone structures at an archaeological site at Oggestorp, near Jonkoping in southern Sweden. The sediment filling the interstices between stones in a wall and a clearance cairn is assumed to have been light exposed during or before construction, and we anticipated that these fill samples were likely to be incompletely bleached, so that the smallest doses would be the most relevant. However, any reworking of the structures, or even later aeolian events, could emplace a small fraction of younger materials, and so there were also likely to be some grains with substantially smaller doses. The dose distributions from such fill samples have been studied using both small aliquots and individual grains of quartz. We present preliminary construction ages for a stone wall and cairn based on these dose distributions, and compare these with independent age constraints derived from OSL ages of associated heated stones and aeolian sand. and from the other archaeological evidence. (C) 2003 Elsevier Science Ltd. All rights reserved.