The fracture pattern of pebbles in lower Old Red Sandstone conglomerates of various localities between Loch Lomond and the North Esk river, Scotland, indicates that the southern component of the principal compression along the Highland Boundary fault was a continuation, during middle Devonian movements, of the Caledonian stress system acting in a northwest to southeast direction normal to the trend of the fault, varying in places to north-northwest-south-southeast.

You do not currently have access to this article.