Moine Supergroup

The Moine Supergroup is a sequence of Neoproterozoic metamorphic rocks that form the dominant outcrop of the Scottish Highlands between the Moine Thrust Belt to the northwest and the Great Glen Fault to the southeast. The sequence is metasedimentary in nature and was metamorphosed and deformed in a series of tectonic events during the Late Proterozoic and Early Paleozoic. It takes its name from A' Mhòine, a peat bog in northern Sutherland.

The main outcrop of the Moine series lies northwest of the Great Glen Fault, structurally above the Moine Thrust to the west forming what is known as the Northern Highlands Terrane. A smaller area of similar rocks that are correlated with these, outcrop within the 'Grampian Terrane' to the southeast of the Great Glen. Moinian rocks are also recognised on Mull, Orkney and Shetland.

The Moine Supergroup has been subdivided into different groups or divisions. The relationship between individual groups in terms of age and stratigraphic equivalence is generally unclear, as they are unfossiliferous due to their age and metamorphic state. They are mostly described in tectonostratigraphic terms referring to their position relative to major Caledonian thrust structures. The Moine is lithologically monotonous, being dominated by psammites (metamorphosed sandstones), making lithostratigraphic correlation extremely difficult.

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