A LOCH’S LITHOLOGY: A PRELIMINARY STUDY OF THE STONE RESOURCES FROM LOCH OF STENNESS AND THEIR RELATIONSHIP TO THE NESS OF BRODGAR AND OTHER SITES WITHIN THE UNESCO’S HEART OF NEOLITHIC WORLD HERITAGE

The Ness of Brodgar is a multi-phased monumental site in the heart of Neolithic Orkney located on a narrow isthmus between the Loch of Harray to the east and the Loch of Stenness to the west. This large site is chiefly composed of well-preserved walls of numerous monumental-scaled structures built from finely laminated sandstones of the Red Sandstone Formation that underlie much of the Orkney Islands. The stones used within the structures display a variety of textures including differences in grain size, grain constituents, and cementation. The source quarry or quarries of these rocks is still unknown. Geophysical surveys of the Loch of Stenness have identified potential submerged quarry sites along a rocky ledge approximately 100 meters from shore and about 2-3 meters in depth extending along the eastern shore near to the Ring of Brodgar and the Ness of Brodgar. Because the lochs to either side of the site have developed in time, due to the impact of rising relative sea-levels, this ledge would have been available as a potential quarry source of flagstone for construction at the Ness of Brodgar and other sites within the UNESCO's Heart of Neolithic World Heritage. This paper reports on a preliminary submarine survey of the submerged ledge to determine basic variation in lithology and potential matching with onshore sites.