... semipelite becomes more common, forming a passage up into the overlying formation. On the top of Beinn a Chaoruinn (NN 386850) a thick, often pink-stained quartzite is taken to mark the base of the Clachaig Formation and the Glen Spean Subgroup. In the type area the Glen Spean Subgroup has been divided...

... area (their figs 3 and 7). In addition in their fig. 7, the ornamentation for the Clachaig Formation is not consistent with previous figures. The ornament presumably combines stratigraphy and rock type and indicates semi-pelite at the base of the Glen Spean Subgroup. The Drumochter Succession...

.... 1). Here the Inverlair Formation oversteps the underlying Clachaig Formation on to the Creag Meagaidh Formation (Figs 1 & 2). Elsewhere in the Grampian Group formational boundaries appear to be transitional. The Appin Group of the study area comprises two subgroups (Fig. 2, Table 1). The older...

... Clachaig and Inverlair Formations in the type area. According to the Grampian Group basin architectural model of Smith et al. (1999 ), the two areas occupied different rift basins and so it is not surprising that they record different environments. The Gaick Psammite Formation and the type area Glen...

...) a lack of along strike variability, internal marker beds, and poor outcrop hamper detailed studies. Ongoing work confirms the suggestion by Glover & Winchester (1989) that the Clachaig Semipelite and Inverlair Psammite formations of the Glen Roy district are broadly equivalent to the Strathtummel...

... of the Steep Belt, oversteps the Clachaig Formation in the vicinity of Creag Pitridh [NN 487 815] and further northwest, near Creag Meagaidh [NN 38 87] on what may be a sub-Inverlair unconformity (Glover et al. 1995) and itself dies out to the northeast. These features mirror the situation to the northwest...

...). In the uppermost parts of the Corrieyairack Basin succession, a change to shallow-water depositional environments was recorded (Clachaig Semipelite Formation and Inverlair Psammite Formation, Glen Spean Subgroup). Fig. 4. Proposed lithostratigraphical correlation for parts of the Grampian Group...

..., metasandstone, metamudstone; semipelite, a quartzite, pelite Grampian:  Beinn Iaruinn Quartzite Fm Feldspathic quartzite, semipelite  Clachaig Semipelite and Psammite Fm Quartzite a  Glen Fintaig Semipelite Fm Feldspathic quartzite  Glen Gloy Quartzite Fm Feldspathic quartzite...