Linear structures and their relation to movement in the Caledonides of Scandinavia and Scotland

Summary The author considers that, although Dr. D. B. McIntyre9s geometrical reconstruction of the structures observed in mid-Strathspey (1951, Q.J.G.S. 107 , 1–22) may be essentially correct, his kinematic interpretation of the structures is open to question. Dr. Mclntyre9s evidence is discussed briefly. Sander9s evidence for his theory of the relation of plane of symmetry to direction of movement is also reviewed. Structures in the Caledonides of Norway cannot be brought into agreement with Sander9s theory, and it is concluded that the theory needs modification. A plane of symmetry may be formed at right angles to a lineation which is parallel to the direction of movement. Linear structures reflect local conditions of deformation and may under certain conditions be formed at any angle with the principal direction of movement. Brief remarks are given on the formation of a lineation and on the general picture of linear structures in the Caledonides. Comments are made on the occurrence of minor linear structures in the Scottish Highlands, and their importance. Variation in trend of linear structures in the Highlands is briefly discussed. It is suggested that when the linear structures of the Highlands are more completely known it may be possible to explain all structures as having been formed during the Caledonian orogeny. The Moinian and the Dalradian may both be Caledonian geosynclinal sediments, corresponding to the Norwegian Sparagmite Formation and Soros Group respectively.