Metabentonites from the Silurian inliers of the southern Midland Valley ofScotland: distribution and geochemistry

A survey of eight Silurian inliers in the southern Midland Valley of Scotla nd has identified four new metabentonite occurrences within the Telychian S tage of the Llandovery, in the Bavelaw Castle, Hagshaw Hills, Lesmahagow an d Girvan Main inliers respectively. The bulk geochemical composition of the metabentonites highlights two broad associations: an intermediate/mafic, slightly alkaline group represented b y the Lesmahagow samples, and a rhyodacitic group comprising samples from t he other inliers surveyed. A potential correlation is proposed between a me tabentonite from the Wether Law Linn Formation of the North Esk inlier and one from the west end of the neighbouring Bavelaw Castle inlier. The unique character of the Lesmahagow metabentonites will assist in further correlat ion studies of Upper Llandovery successions.