above an angular unconformity over various parts of the Torridon Group and locally over the Lewisian. It is a sequence of mainly quartz arenites. The lowermost part of the Eriboll Formation, the Basal Quartzite Member, is often pebbly at its base. The overlying Pipe Rock Member is a distinctive quartz arenite with many white weathering skolithos trace fossils that act as strain markers in areas of more ductile deformation. The uppermost two parts of the Ardvreck Group form the An t-Sron Formation, with the dolomitic Fucoid Beds Member being overlain by the quartz arenites of the Salterella Grit Member. The succeeding Durness Group consists mainly of dolomites, with some limestone and chert. The distinctive character of this sequence enabled detailed mapping, even in areas of relatively poor exposure and allowed sections repeated by thrusting to be recognised. Moine Supergroup The Moine Supergroup, like the Torridonian, is of Neoproterozoic age and possibly a lateral equivalent of that unit. Near the Moine Thrust all of the Moine rocks form part of the Morar Group, which forms the lowest tectonostratigraphic unit of the Moine. Individual thrusts In addition to the Sole Thrust at the base of the northern section of the structure and the Moine Thrust at the top of the belt, many other thrust faults are developed, some of which are large enough to be named and mapped more regionally. The thrust sheet carried by each thrust is named after the thrust beneath it, although the term "nappe" is also used. Moine Thrust The Moine Thrust in the strict sense is the uppermost thrust in the belt and the one that carries the most displacement. In all cases it carries rocks of the Moine Supergroup over rocks of the Hebridean Terrane. Unlike the other thrusts, there is a broad zone (up to 600 m in thickness) of the Moine in the hanging-wall that is intensely deformed into mylonite, indicating that it originated at a significantly deeper crustal level. Total displacement on this one structure has been estimated as several tens of kilometres based on the change in crustal level and the thickness of mylonites developed. In its central section, south of the Assynt Window, it becomes the sole thrust structure, before the Kinlochewe Thrust branches off to the south. Sole Thrust This thrust forms the base of the belt from Eriboll to the southern end of the Assynt Window where it merges