Abstract

Dr D. Powell said he was intrigued that the Morar slide invoked by Kennedy in 1955 to explain the structure of the Morar area had been, in part at least, reinstated. Both Lambert in 1958 and the speaker in 1964 indicated that there is no evidence in south Morar for the Morar slide in the position postulated by Kennedy.

Powell in 1966 had, however, given evidence viz., attenuation of stratigraphic units and rotation of local second phase fold structures, for the existence of a zone of tectonic discontinuity both within and immediately below the outcrop of the Morar Striped and Pelitic Group in SE Morar, in an analogous position to that which Drs Poole and Spring now, and Johnstone et al. in 1969, suggest for the Knoydart slide. In view of this could the authors give details of the behaviour of tectonic structures across the Ladhar Bheinn Pelitic Group-Barrisdale Psammitic Group contact?

Since 'slides' such as that in SE Morar may be zones or planes of strain discontinuity resulting from differences in behaviour during deformation of thick psammite and adjacent pelitic units and are thus likely to follow contacts between such rock types, could the authors detail the evidence for the down-cutting of the Knoydart slide into the Lower Morar Psammite across Loch Nevis and elsewhere?

Dr Spring pointed out in reply that the slide now proposed in an area which could broadly be called the NE quadrant of the Morar Antiform is at a different, higher level than the

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