The Cnoc nam Broc site offers excellent opportunities for examining one of the major structures of the Moine Thrust Belt, the Kishorn Thrust Sheet, together within its relationship to surrounding thrust structures. Torridonian sediments within the sheet have a variety of deformation states, locally highly sheared but recognisably unconformable upon their Lewisian basement, and as highly fractured, thrust-bounded slices. The footwall consists of folded and thrust Cambrian strata that show remarkable variations in structure along strike. The activation of detachment horizons within the stratigraphic pile, notably at the base of the fucoid beds and just within the Durness Group, has allowed the development of two imbricate thrust systems. The structurally lower of these, imbricating the An t-Sron Group, form last thereby folding and breaching the structurally higher imbricate system within the Durness Group together with a far-travelled sheet of pipe rock. The site is therefore an excellent place to study not only lateral variations in thrust geometry but also there evidence necessary to deduce the relative timing of thrust structures. It has the additional advantage of rare outcropping examples of the post-Caledonian faults that have accommodated Mesozoic crustal extension, an episode that is reflected in the morphotectonics of NW Scotland.
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