Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

Journal of the Geological Society

This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Search for Related Content GeoRef GeoRef Citation

Discussion of the structural setting and tectonic significance of the Glen Dessary Syenite, Inverness-shire

MR A. W. BAIRD writes: Roberts, Smith & Harris (1984) have produced a significant piece of structural mapping in Glen Dessary but I cannot agree with their interpretation of its regional significance. I propose an alternative which does not involve the unlikely situation of regional scale vertical extension, and is more in keeping with the structural history obtained from studies nearby (e.g. Baird 1982; Powell et al. 1981).

Roberts et al. describe a series of D₃ major folds with sub-vertical axial plane traces. The D₃ Glen Dessary Synform has an intensely curvilinear hinge line with a sub-vertical extension (X) direction within its fold axial plane. All the D₃ major folds east of the Glen Dessary Synform have sub-horizontal fold hinge lines. They attribute the change of hinge line orientation and development of curvilinear folds to a rapid increase in the amount of D₃ strain westwards, and they link this strain variation to the generation of the ‘steep belt’, with the Loch Quoich line representing the eastern limit of intense D₃ strain and upright reworking.

The post-D₂ Glen Dessary Syenite was intruded at 456 ± 5 Ma. (van Breemen et al. 1979). Elsewhere in the Western Moine schists, D₂ is regarded as a Precambrian (Grenville) tectonic event (Brook et al. 1976; Brook et al. 1977; Brewer et al. 1979; Powell et al. 1983). Therefore Roberts et al. argue that the production of the steep belt during D₃ deformation must represent the first Lower Palaeozoic structural reworking of the Moine rocks. However

...

This 250-word extract was created in the absence of an abstract.

This article has been cited by other articles:

				B. Harte Lower Palaeozoic metamorphism in the Moine-Dalradian belt of the British Isles Geological Society, London, Special Publications, January 1, 1988; 38(1): 123 - 134. [Abstract] [PDF]

				N. M. S. Rock, R. Macdonald, S. E. Drewery, R. J. Pankhurst, and M. Brook Pelites of the Glen Urquhart serpentinite-metamorphic complex, west of Loch Ness (Anomalous local limestone-pelite successions within the Moine outcrop: III) Scottish Journal of Geology, October 1, 1986; 22(2): 179 - 202. [Abstract] [PDF]