Abstract
The primary goal of this study is to describe and characterize the anomalous Buchan Coast metamorphic sequence in NE Scotland in relation to the classic Buchan-type sequence (Crd-And-Sil-Kfs) exemplified by the Ythan River metamorphic sequence. The Buchan Coast sequence is comprised of the mineral sequence staurolite – cordierite – andalusite – sillimanite – K-feldspar.
Studies have established the peak of metamorphism in the Grampian Orogeny to be ~ 470 Ma but there is contention about the timing of origin of the Cowhythe Gneiss, found in the Buchan Coast sequence. Monazite U/Pb chemical dating was performed to determine the age of metamorphism in the Buchan Coast and the Ythan River sequences as well as the age of the Cowhythe Gneiss. The dating indicated an average age of 424±20 Ma for the two metamorphic sequences, with an average age of 474±14 Ma for the Cowhythe Gneiss.
