STRATIGRAPHY
The only unit in which it was possible to produce a stratigraphy was the Camas breccia. No evidence of way-up structures could be observed in any of the Gairloch supracrustal Group and only one major boundary was observed it is not possible to show the relationship of one unit to another i.e. whether a contact is Normal, Unconformable or Tectonic.
It could however be shown that the Camas breccia lies with angular unconformity on the Torr schist and the Gairloch schist, and similarly the Druim breccia overlies the Garbh amphibolite and Tollie Gneiss with angular unconformity. Park (1970) states that the relationship of the Tollie gneiss and Garbh amphibolite is tectonic, as evidenced by the Creag Bhan crush belt in the valley of the Allt Eas Ghairbh Ghraird (NGR 82107757). In the area mapped, the exposure was poor and the crush belt could not be observed, therefore the assertion made by Park (op. cit.) was unable to be confirmed or rejected.
Park (in - Regional guide to the North West Highlands) has also stated that the Garbh amphibolite and the Achlais amphibolite are the same unit, (i.e. each are limbs of an isoclinal fold in which the closure may be observed several kilometres to the north). It was not possible to substantiate this assertion, indeed on the field evidence gathered (mineralogy and textures in the two lithologies) it is suggested that the two units represent separate rock types with the grain size and mineralogy being very different (See unit descriptions).
Thus the stratigraphy within the metamorphic complex could not be deduced (mainly through lack of way-up structures and poor exposure of boundaries) in the limited area mapped,
The limited amount of Camas breccia along the coast was logged and a stratigraphy was worked out. All of these deposits are believed to belong to the Diabeg formation of the Torridonian (Williams 1966). Way-up structures include graded bedding and crossbedding, which show the units to be the right way up. It was not possible to correlate the Druim breccia to the units along the coast. No way-up structures were observed in the Druim breccia but intuitively it seems unlikely-that these beds are inverted.
It would seem reasonable on the basis of lithology that the Druim breccia also belongs to the Diabeg formation of the Torridonian.
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