Figure and tables

(Front cover)

The Dalradian rocks of the South-West Highlands — introduction

(Figure 1) Simplified geological map of the Dalradian rocks in the South-west Highlands of Scotland, showing the axial traces of the major folds according to Roberts and Treagus (1977). Place-names in capitals give the locations of the various field-areas covered by this series of excursion guides. Note that the stratigraphic units correspond to the various sub-groups as given in (Table 1) and (Figure 2).

(Figure 2) Diagrammatic cross-sections through the Dalradian rocks in the South-west Highlands of Scotland, showing the structural relations of the major folds established in (Figure 1). Arrows give the facing of the early folds. These sections have been drawn on the assumption that the upper limb of the Ardrishaig–Aberfoyle Anticline is much less deformed than the lower limb.

(Table 1) Lithostratigraphy compiled for the Dalradian rocks in the South-west Highlands of Scotland after Harris and Pitcher (1976).

1 The Dalradian rocks of Rosneath and south-east Cowal

(Figure 1) Geological map of Rosneath and south-east Cowal (after sheets 29 (Rothesay) and 30 (Glasgow) of the Geological Survey of Scotland). See (Figure 1) of the introductory guide for the axial traces of the major folds recognized in this area.

(Figure 2) Geological map (after Roberts 1966) of the southern end of the Rosneath Peninsula showing the various lithologies developed within the Beinn Bheula Schists, the Dunoon Phyllites and the Bullrock Greywacke.

2 The Dalradian rocks of Knapdale and North Kintyre

(Figure 1) Geological map of Knapdale and North Kintyre (after sheets 28 (Jura) and 29 (Rothesay) of the Geological Survey of Scotland). See figure 1 of the introductory guide for the axial traces of the major folds recognized in this area.

(Figure 2) Left: Geological map of the section between Kilmory Bay and the Point of Knap (Excursion 1, localities 1–14). Right: Geological map of the section between Barmore Island and Tarbert (Excursion 2, localities 17–24).

3 The Dalradian rocks of the west coast of the Tayvallich peninsula

(Figure 1) Guide to the localities described in the text.

(Figure 2) Vertical and lateral variations in a basic submarine lava flow.

(Figure 3) Stratigraphic column at Port nan Clach Cruinn. Key 1 Vesicular lava with basal pipe amygdales. Load structures cause sediment to be squeezed upwards into lava. Toes of lava project downwards and northwards into the sediment causing minor fold disturbances. 2 Interbedded cream limestone (1–3 cm) and cream calcareous phyllite (0.5–1 cm). 3 Channel filled by limestone containing boulders of grey limestone in a matrix charged with angular fragments of quartz. Whole unit is cross-bedded, indicating derivation from south. 4 Pure grey limestone with beds 1–10 cm thick. 5 Parallel laminated (0.5–1 cm) limestone. 6 Graded limestone with fragments of quartz (1–1.5 cm) and black calcareous slate. Channelled base trending 110°. Intruded from below by a sedimentary dyke of 7. 7 Laminated (0.2–2 cm) limestone with sand-sized quartz fragments. 8 Conglomerate with boulders of dark grey limestone. 9 As 7. 10 Conglomerate of rusty weathering black limestone with largest fragments measuring 100 × 50 cm. 11 As 7. 12 Grey limestone with fragments (0.5–1 cm) of malachite and quartz. 13 As 7 with ripple marked base.

4 The Dalradian rocks of Jura

(Figure 1) General map of the area described in this guide. The Ordnance Survey 1:50,000 sheet 61 covers the whole of Jura.

(Figure 2) Stratigraphical relationships of the formations described in this guide.

(Figure 3) General map of the area described in text.

5 The Dalradian rocks of Lunga, Luing and Shuna

(Figure 1) General map of the area described in this article.

(Figure 2) Guide to localities described in the text

6 The Dalradian rocks of the northern Loch Awe district

(Table 1) Stratigraphic sequence for the northern Loch Awe District after Borradaile (1973). + = Lower Cambrian, + + = Late Precambrian, from the micropalaeontological evidence of Downie et al. (1971).

(Figure 1) Diagrammatic cross-section of the major structures of the Iltay Nappe Complex on which are indicated the approximate structural positions of the localities described in this guide. The stippled regions in this cross-section correspond to the areas illustrated by geological maps (Kilmelford), 4 (Kilchrenan) and 5 (Loch Avich). The localities at Oban and Strone Point are, respectively, localities 11 and 12.

(Figure 2) Distribution of the principal lithologies of the Dalradian rocks in the Northern Loch Awe District (after Borradaile, 1973). N.B. The maximum number of passengers that may be carried in one vehicle on certain roads is as follows:(a) the road along the north shore of Loch Melfort: 15 persons. (b) The road from Loch Melfort to Loch Awe passing Loch Avich: 15 persons.(c) The road along the West shore of Loch Awe, south from Kilchrenan: 21 persons. No restrictions exist for the other roads illustrated.

(Figure 3) Geological map of the Kilmelford district with localities 1 and 2 indicated. Areas in which the Dalradian rocks are less well exposed have been left unornamented and outcrops of post tectonic igneous intrusions have been omitted.

(Figure 4) Geological map of the Kilchrenan district with localities 3, 4, 5, 6 and 7 indicated. Areas in which the Dalradian rocks are poorly exposed have been left unornamented and outcrops of many minor post-tectonic igneous intrusions have been omitted.

(Figure 5) Geological map of the ground to the North-East of Loch Avich with localities 8, 9 and 10 indicated. Areas in which the Dalradian rocks are poorly exposed have been left unornamented and outcrops of minor post-tectonic igneous intrusions have been omitted.

7 The Dalradian rocks of the Loch Leven area

(Table 1) Stratigraphy of the Loch Leven area

(Figure 1) Geological map of the Loch Leven area showing the lithostratigraplry. Modified from sheet 53 (Ben Nevis) of the Geological Survey of Scotland. See (Figure 1) of the introductory guide for the axial traces of the major folds recognized in this area.

(Figure 2) Diagrammatic cross-section through the Moine and Dalradian rocks from Loch Linnhe (West) to the Blackwater Reservoir (East). Abbreviations as follows: FWSI Fort William Slide; Asc Appin Syncline; TMAc Tom Meadhoin Anticline; BaSc Ballachulish Syncline; SBSf Stob Bhan Synform; MnGF Mam na Gualainn Folds; BaSI Ballachulish Slide; KAc Kinlochleven Anticline; MSc Mamore Syncline; KAf Kinlochleven Antiform; MAc Mamore Anticline; BSf Blackwater Synform; BAf Blackwater Antiform.

(Figure 3) Geological map of the Ardsheal peninsula (Excursion 1, localities 1–5).

(Figure 4) Geological map of the Onich section (Excursion 2, localities 6–16).

(Figure 5) Geological map (after Roberts, 1976) of the area between Callert and Stob Bhan (inset), (Excursion 3–5, localities 17–27).

(Figure 6) Geological map (after Treagus, 1974) of the Kinlochleven area (Excursion 6, localities 28–33).