Moine-Lewisian relations at Glenelg, Inverness-shire

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Abstract
Summary: Metamorphosed psammitic and politic sediments of the Moine Series, together with a complex group of gneisses of Lewisian age, alternate in bands. A study of the relations of the individual members of the Lewisian complex shows that there has been an early phase of migmatization (probably of Scourian age) followed by a period of basic dyke intrusion. Neither of these events is shared by the adjacent Moine rocks. New evidence indicates that the most extensive area of Moine rocks occurs in a major antiformal core and lies structurally beneath the Lewisian gneisses, whilst the alternating Lewisian and Moine bands represent slices of tectonic origin which came into position before the development of this antiform. Two sets of major folds have been recognized, and the effects of their interference are discussed. The axial planes of the first folds originally dipped to the east. A second set of major folds with south-easterly dipping axial planes was superimposed across the early folds, distorting the early folds and their associated minor structures. This distortion is a combination of deformation resulting from a simple refolding of the first-fold limbs together with a plastic deformation.