The Appin Group is a thick sequence of metamorphosed Neoproterozoic sedimentary rocks that outcrop across the Central Highlands of Scotland, east of the Great Glen.
It forms a part of the Dalradian Supergroup.
It is divided into three subgroups each consisting of multiple named formations.
In stratigraphic order i.e. youngest at the top, these are: Blair Atholl Subgroup Ballachulish Subgroup Lochaber Subgroup This whole succession reflects alternate periods of deepening and filling of the sedimentary basin.
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