Anderson, F.W. and Dunham, K.C. 1966. The geology of Northern Skye

Figures and plates

Figures

(Figure 1) Sketch map showing distribution of main groups of rocks in Northern Skye. Figures indicate margins of one-inch sheets

(Figure 2) Generalized vertical section of sedimentary and volcanic rocks exposed in Northern Skye

(Figure 3) Section in sea-cliff at Fiurnean, 4 miles N.N.E. of Portree

(Figure 4) Sections showing the sequence of strata in the Concretionary Sandstones, Lower 'Ostrea' Beds, Ostracod Limestones, Mottled Clays, Upper 'Ostrea' Beds, Oxford Clay, Corallian and Kimmeridge Clay

(Figure 6) Section in sea-cliff between Upper Tote and Inver Tote

(Figure 7) Section in sea-cliff between Drum Dearg and Loch Mealt fall

(Figure 8) Map of Jurassic strata in Staffin Bay, coast east of Bligg. Grid references in square brackets

(Figure 9) Map of Jurassic strata in Staffin Bay, coast east of Loch Learn nam Bradh. Grid references in square brackets

(Figure 10) Map of Jurassic strata in Staffin Bay, coast east of Loch Langaig. Grid references in square brackets

(Figure 11) Map of Jurassic strata in Staffin Bay, coast south-east of Flodigarry Hotel. Grid references in square brackets

(Figure 12) Correlation of the Jurassic strata exposed in Stain Bay. Grid references in square brackets

(Figure 13) Sketch-map showing the outcrops of the main lava-groups and section showing their mutual relationships. The suggested former limits of the groups are projected from the known thickness of the present day remnants. Intervals, between extrusive episodes are represented in many places by plant-bearing sediments and tuffs.

(Figure 14) Section showing the behaviour of part of the Tertiary sill-complex at Eist

(Figure 15) Modes of a suite of specimens collected at intervals in the central chimney cutting the Meall Tuath upper sill, Rubha Hunish. Density determinations and estimates of magnesia and lime are given for comparison. Densities by G. Wilson, chemical determinations by R. Lambert, Durham University Geology Department, 1962

(Figure 16) Plot of compositions of normative feldspars in Hebridean lavas and sills. Circles lavas; triangles, sills; black circle, dyke; crosses, feldspars from Druim na Criche mugearite, analysed by Muir and Tilley 1961. P, tholeiitic pillow lava; S, normative feldspar in glass from palagonite tug. Numbers correspond with those for Fig 17. U^A, allivalite dyke. List of chemical analyses used in Figs. 16 & 17. 1. Picrite, base of cliff S. of Garbh Eilean, Shiant; Walker 1930, p. 371. 2. Picrite, top of cliff W. of Camas Mor, Skye; Walker 1932, p. 246. 3. Picrite-basalt, An Camach, Strathaird, Skye; Almond 1964. 4. Olivine-dolerite, 30 ft above beach, S. face of Garbh Eilean, Shiant; Walker 1930, p. 371. 5. Fine-grained basalt, 100 yd N.W. of Loch Cuil na Creig, Skye; King 1953, p. 365 6. Olivine-basalt, scarp E. of Dunmull Toberdornan Townland, 3 miles S.E. of Portrush, Northern Ireland; Patterson 1955, p. 103. 7. Ophitic basalt, 50 yd W. of Strollamus Quarry, Skye; King 1953, p. 365. 8. Olivine-basalt, scarp S. of County Road, Ballykeel Townland, 1¾ miles E.S.E. Portrush, N. Ireland; Patterson 1955, p. 103. 9. Basalt, E. side Rubha Dearg, 1 mile W. of Loch Aline, Morven; Bailey and others 1924, p. 15. 10. Olivine-dolerite, summit of Ben Lee N.W. of Loch Sligachan; Harker 1904, p. 248. 11. Olivine-basalt, flow 1, Ben Meabost, Skye; Almond 1960. 12. Olivine-basalt, near bridge over Allt Fionnfhiachd, Drynoch, Skye; Harker 1904, p. 31. 13. Olivine-basalt, Creag Mor, Skye; (p. 103). 14. Olivine-dolerite, Loch Mealt, near Waterfall, Skye; Walker 1932, p. 247. 15. Basalt, ⅓ mile N.N.E. Pennycross House, Mull; Bailey and others 1924, p. 15 16. Basalt, cliff 200 yd W. of Loch Eilean, Morven; Bailey and others 1924, p. 15. 17. Olivine-basalt, Achtalean 2¼ miles N.N.W. of Portree, Skye; Tilley and Muir 1962, p. 212. 18. Basalt, Orval, Rhum; Harker 1908, p. 57. 19. Olivine-dolerite, 500 yd N. of Tam, Broc-bheinn, 4 miles N.N.W. of Sligachan, Skye; Harker 1904, p. 248. 20. Trachybasalt, An Carnach, Strathaird, Skye; Almond 1960. 21. Dolerite-mugearite, S. of Fionn-Chro, Rhum; Harker 1908, p. 130. 22. Mugearite-basalt, River Rha, above Uig, Skye; Muir and Tilley 1961, p. 190. 23. Doleritic mugearite, Eilean a'Bhaird, Canna; Harker 1908, p. 130. 24. Mugearite, cap of Hartaval, Skye; (p. 118). 25. Mugearite, Druim na Criche, near Mugeary, Skye; Muir and Tilley 1961, p. 190. 26. Mugearite (Benmoreite), 290 yd E. of Kinloch Hotel, Mull; Bailey and others 1924 p. 27. 27. Mugearite-trachyte (Benmorerite), Totardor, Skye; Muir and Tilley 1961, p. 190. 28. Trachyte, Ardnachross Vent, ¼ mile W. Rubha an t-Sean-Chaisteil, Mull; Bailey and others 1924, p. 27. 29. Trachyte, Ros a'Mheallain, Skye; (p. 118). 30. Trachyte, Vent, Braigh a'Choir' Mhoir, W. of Salen, Mull ; Bailey and others 1924, p. 27.

(Figure 17) Variation diagram for the Alkaline Olivine-basalt lavas and minor intrusions. Black spots, Skye lavas; open circles, other Hebridean lavas; crosses, Antrim plateau basalts; open squares, North Skye and Shiant sills; TB trachybasalt MB mugearite-basalt; MT mugearite-trachyte. Picrite and picrite-basalt fall in a field limited by the line for D = 16–5 and are considered to be accumulative rocks. List of chemical analyses used in Figs. 16 & 17. 1. Picrite, base of cliff S. of Garbh Eilean, Shiant; Walker 1930, p. 371. 2. Picrite, top of cliff W. of Camas Mor, Skye; Walker 1932, p. 246. 3. Picrite-basalt, An Camach, Strathaird, Skye; Almond 1964. 4. Olivine-dolerite, 30 ft above beach, S. face of Garbh Eilean, Shiant; Walker 1930, p. 371. 5. Fine-grained basalt, 100 yd N.W. of Loch Cuil na Creig, Skye; King 1953, p. 365 6. Olivine-basalt, scarp E. of Dunmull Toberdornan Townland, 3 miles S.E. of Portrush, Northern Ireland; Patterson 1955, p. 103. 7. Ophitic basalt, 50 yd W. of Strollamus Quarry, Skye; King 1953, p. 365. 8. Olivine-basalt, scarp S. of County Road, Ballykeel Townland, 1¾ miles E.S.E. Portrush, N. Ireland; Patterson 1955, p. 103. 9. Basalt, E. side Rubha Dearg, 1 mile W. of Loch Aline, Morven; Bailey and others 1924, p. 15. 10. Olivine-dolerite, summit of Ben Lee N.W. of Loch Sligachan; Harker 1904, p. 248. 11. Olivine-basalt, flow 1, Ben Meabost, Skye; Almond 1960. 12. Olivine-basalt, near bridge over Allt Fionnfhiachd, Drynoch, Skye; Harker 1904, p. 31. 13. Olivine-basalt, Creag Mor, Skye; (p. 103). 14. Olivine-dolerite, Loch Mealt, near Waterfall, Skye; Walker 1932, p. 247. 15. Basalt, ⅓ mile N.N.E. Pennycross House, Mull; Bailey and others 1924, p. 15 16. Basalt, cliff 200 yd W. of Loch Eilean, Morven; Bailey and others 1924, p. 15. 17. Olivine-basalt, Achtalean 2¼ miles N.N.W. of Portree, Skye; Tilley and Muir 1962, p. 212. 18. Basalt, Orval, Rhum; Harker 1908, p. 57. 19. Olivine-dolerite, 500 yd N. of Tam, Broc-bheinn, 4 miles N.N.W. of Sligachan, Skye; Harker 1904, p. 248. 20. Trachybasalt, An Carnach, Strathaird, Skye; Almond 1960. 21. Dolerite-mugearite, S. of Fionn-Chro, Rhum; Harker 1908, p. 130. 22. Mugearite-basalt, River Rha, above Uig, Skye; Muir and Tilley 1961, p. 190. 23. Doleritic mugearite, Eilean a'Bhaird, Canna; Harker 1908, p. 130. 24. Mugearite, cap of Hartaval, Skye; (p. 118). 25. Mugearite, Druim na Criche, near Mugeary, Skye; Muir and Tilley 1961, p. 190. 26. Mugearite (Benmoreite), 290 yd E. of Kinloch Hotel, Mull; Bailey and others 1924 p. 27. 27. Mugearite-trachyte (Benmorerite), Totardor, Skye; Muir and Tilley 1961, p. 190. 28. Trachyte, Ardnachross Vent, ¼ mile W. Rubha an t-Sean-Chaisteil, Mull; Bailey and others 1924, p. 27. 29. Trachyte, Ros a'Mheallain, Skye; (p. 118). 30. Trachyte, Vent, Braigh a'Choir' Mhoir, W. of Salen, Mull ; Bailey and others 1924, p. 27.

(Figure 18) Plots of iron-oxide-magnesia ratio and iron oxide-content against silica. Dotted line, Skaergaard liquids (Wager 1960); full line, Hebridean alkaline olivine-basalt suite; dot-dash, average tholeiites (Nockolds 1954); dashes, Cascade volcanics (Osborn 1959)

(Figure 19) Sketch-map showing movement of ice and other glacial features in Skye

(Figure 20) Glacial retreat stages in Trotternish, Isle of Skye. BC, Bealach a'Chaol-reidh; BL, Beinn an Laoigh; BR, Beinn an Righ; BS, Beinn a'Sga; CC, Creag Chragach; CL, Creag an Locha; Gil, Glen Hinnisdal; GU, Glen Uig; RH, River Haultin; RR River Romesdal

(Figure 21) The Bracadale–Edinbain late-Glacial lake system at the 550-ft retreat stage

(Figure 22) Section of the Quirang Landslip

(Figure 23) Section of The Storr Landslip

Plates

(Plate 1) A. The Storr from the south;. part of the Trotternish lava-scarp. Landslipped lavas and Jurassic sediments form the ground to the right of the escarpment. In the foreground a glacially eroded hollow in Jurassic sediments is occupied by the two lochs Fada and Leathan, which supply water for the Bearreraig Hydro-electric Station. (D3173, replaces MN20706); B. Landslip topography south of Flodigarry Hotel. In the foreground slipped masses of Tertiary lava and Jurassic sediments. In the distance the headland of Rubha Garbhaig is of Tertiary dolerite sills in Jurassic sediments.(D3172, replaces MN20704); C. Staffin Bay from the north. On the foreshore are upper Jurassic sediments. In the middle distance Staffin Point (An Corran) is formed by two dolerite sills with Jurassic sediments between them. Behind the storm beach the 25-ft and 50-ft beach flats are well seen and correspond with the rock notches seen in An Corran. (D3171, replaces MN20705) Frontispiece

(Plate 2) A. Bearreraig, six miles north-north-east of Portree. Inferior Oolite sandstone giving rise to waterfall. (C2241) B. Lyndale Point, 100 yd from shore, 1530 yd north-northwest of Lynedale House. Dolerite dyke showing columnar jointing. (C3919)

(Plate 3) A. Bearreraig Bay, 6½ miles north-north-east of Portree. Columnar sill of dolerite overlying Inferior Oolite. (C2244) B. Coast, south of Mealt Waterfall, looking north from Valtos. Great Estuarine Series with intruded sills of dolerite. (C3898)

(Plate 4) The Quirang, looking north-east from Tug road. Escarpment of Tertiary lavas with extensive area of landslipped masses of Tertiary volcanic material. Staffin is on the extreme right. (C3899–3900)

(Table 1) Analyses of palagonite, glass and tuff.

(Table 2) Analyses and norms of sidermelane, pillow lava and tholeiitic basalts.

(Table 3) Lava types in Northern Skye.

(Table 4) Analysis of Hebridean basalt, amygdaloid and bole.

(Table 5) Minerals in lavas exposed at the Storr and Rubha na h-Airde Glaice (One-inch Sheet 80, six-inch Sheet Skye 18 N.W.).

(Table 6) Analyses and norms of Hebridean type basalts, Skye.

(Table 7) Minerals in lavas exposed at Biod a'Ghoill, Score Horan, Vaternish.

(Table 8) Analyses of mugearites and trachyte.

(Table 9) Analysis of porphyritic mugearite.

(Table 10) Analyses of dolerites and related rocks.

(Table 11) Norms and modes of dolerites and related rocks./p>

(Table 12) The dykes of North Skye./p>

(Table 13) Analyses and norms of allivalite and eucrite.

(Table 14) Average Hebridean basalt, mugearite and trachyte.

(Table 15) Calculated compositions of subtracted differentiates.

(Table 16) Calculated assimilation by mugearite and trachyte.

(Figure 1) Sketch map showing distribution of main groups of rocks in Northern Skye. Figures indicate margins of one-inch sheets.

(Figure 2) Generalized vertical section of sedimentary and volcanic rocks exposed in Northern Skye.

(Figure 3) Section in sea-cliff at Fiurnean, 4 miles N.N.E. of Portree.

(Figure 6) Section in sea-cliff between Upper Tote and Inver Tote.

(Figure 7) Section in sea-cliff between Drum Dearg and Loch Mealt fall.

(Figure 8) Map of Jurassic strata in Staffin Bay, coast east of Bligg. Grid references in square brackets.

(Figure 9) Map of Jurassic strata in Staffin Bay, coast east of Loch Learn nam Bradh. Grid references in square brackets.

(Figure 10) Map of Jurassic strata in Staffin Bay, coast east of Loch Langaig. Grid references in square brackets.

(Figure 11) Map of Jurassic strata in Staffin Bay, coast south-east of Flodigarry Hotel. Grid references in square brackets.

(Figure 12) Correlation of the Jurassic strata exposed in Stain Bay. Grid references in square brackets.

(Figure 14) Section showing the behaviour of part of the Tertiary sill-complex at Eist.

(Figure 19) Sketch-map showing movement of ice and other glacial features in Skye.

(Figure 21) The Bracadale–Edinbain late-Glacial lake system at the 550-ft retreat stage.

(Figure 22) Section of the Quirang Landslip.

(Figure 23) Section of The Storr Landslip.

(Table 1) Analyses of palagonite, glass and tuff.

(Table 2) Analyses and norms of sidermelane, pillow lava and tholeiitic basalts.

(Table 3) Lava types in Northern Skye.

(Table 4) Analysis of Hebridean basalt, amygdaloid and bole.

(Table 5) Minerals in lavas exposed at the Storr and Rubha na h-Airde Glaice (One-inch Sheet 80, six-inch Sheet Skye 18 N.W.). .

(Table 6) Analyses and norms of Hebridean type basalts, Skye.

(Table 7) Minerals in lavas exposed at Biod a'Ghoill, Score Horan, Vaternish.

(Table 8) Analyses of mugearites and trachyte.

(Table 9) Analysis of porphyritic mugearite.

(Table 10) Analyses of dolerites and related rocks.

(Table 11) Norms and modes of dolerites and related rocks./p>.

(Table 12) The dykes of North Skye./p>.

(Table 13) Analyses and norms of allivalite and eucrite.

(Table 14) Average Hebridean basalt, mugearite and trachyte.

(Table 15) Calculated compositions of subtracted differentiates.

(Table 16) Calculated assimilation by mugearite and trachyte.