Site name
|
GCR selection criteria
|
Lewisian Block
|
|
Lewisian of the Outer Hebrides Network Chapter 2
|
|
Roineabhal, South Harris
|
Representative of the Palaeoproterozoic South Harris Igneous Complex. Exceptional example of a metamorphosed layered gabbro-anorthosite intrusion, the largest in the British Isles. Internationally important for the understanding of Palaeoproterozoic magmatism and tectonics.
|
Na Buirgh (Borve), South Harris
|
Representative of Palaeoproterozoic elements of the Lewisian Gneiss Complex of the Outer Hebrides, including the South Harris Igneous Complex, the metasedimentary and metavolcanic rocks of the Langavat Belt and the Uig Hills–Harris Granite Vein-Complex.
|
North Pabbay, Sound of Harris
|
Representative of the variation in intensity of Laxfordian deformation and metamorphism across a lithological boundary in the Lewisian Gneiss Complex.
|
North Uist Coast
|
Representative of Laxfordian structures in the Lewisian Gneiss Complex. Exceptional examples of fold and boudinage structures on a variety of scales, mainly affecting intrusions of the 'Younger Basic' Suite.
|
Gearraidh Siar (Garry-a-siar) and Baile a' Mhanaich (Balivanich), Benbecula
|
Representative of the variation in intensity of Laxfordian deformation and metamorphism across areas of contrasting lithology. Also representative of the structural relationships of the 'Younger Basic' Suite. Internationally important for the understanding of the scale and processes of Laxfordian reworking in the Lewisian Gneiss Complex.
|
Rhughasinish, South Uist
|
Representative of the Palaeoproterozoic 'Younger Basic' Suite. Exceptional example of a composite mafic–ultramafic intrusion.
|
Loch Sgioport (Skipport), South Uist
|
Representative of Scourian meta-igneous and metasedimentary gneisses, and members of the 'Older Basic' and 'Younger Basic' suites, which have been relatively unaffected by Laxfordian reworking.
|
Cnoca Breac (Rubh' Aird-mhicheil), South Uist
|
Representative of the mafic and ultramafic intrusive rocks of the 'Older Basic' Suite. Exceptional example of an Archaean layered mafic–ultramafic body.
|
Leinis (Leanish), Barra
|
Representative of early Scourian gneisses, a variety of late-Scourian intrusions, and dykes of the 'Younger Basic' Suite, which are exceptional in that they have not suffered significant Laxfordian reworking.
|
Cnoc an Fhithich (Aird Grèin)
|
Representative of features related to the Outer Hebrides Fault Zone. Exceptional examples of pseudotachylite veins and breccias.
|
Lewisian of the Scottish mainland Network — Chapter 3
|
|
Badcall
|
Representative of the Scourian features of the mainland Lewisian Gneiss Complex, including exceptional examples of gabbroic and tonalitic granulite-facies gneisses. Representative of the Scourie Dyke Suite. Internationally important as the type locality for the Badcallian event, and also as one of the first localities in the world to be studied in detail using isotopic dating techniques.
|
Scourie Mor
|
Representative of the Scourian features of the mainland Lewisian Gneiss Complex, including exceptional examples of mafic and ultramafic bodies that have undergone granulite-facies metamorphism.
|
Sìthean Mòr
|
Representative of metasedimentary gneisses of the mainland Lewisian Gneiss Complex that have been metamorphosed to granulite facies.
|
Scourie Bay
|
Representative of the Scourie Dyke Suite.
|
Tarbet to Rubha Ruadh
|
Representative of the Laxford Front, illustrating the transition from Scourian gneisses of the Central Region to those affected by Inverian and Laxfordian reworking to the north. Internationally important as one of the first locations at which an episode of mafic dyke emplacement was used to separate tectonic events, creating a type of 'pseudo-stratigraphy'.
|
Site name
|
GCR selection criteria
|
Loch Drumbeg
|
Representative of the mafic–ultramafic bodies that are believed to be the oldest parts of the Lewisian Gneiss Complex.
|
An Fharaid Mhòr to Clachtoll
|
Representative of the Inverian event in the mainland Lewisian Gneiss Complex, including the Canisp Shear Zone, an exceptional example of an Inverian shear-zone reworked during the Laxfordian event. Internationally important as the type locality for the Inverian event.
|
Grutinard River
|
Representative of the transition from Scourian gneisses of the Central Region to those affected by Inverian reworking to the south.
|
Creag Mhòr Thollaidh
|
Representative of the Laxfordian Gairloch Shear Zone and of the large scale Tollie Antiform. Exceptional example of a Laxfordian shear-zone, recognizable by the increasing intensity of deformation of Scourie dykes across the area.
|
Kerrysdale
|
Representative of the Kerrysdale unit of the Loch Maree Group, and of shear zones within the Loch Maree Group.
|
Flowerdale
|
Representative of the Flowerdale marble belt of the Loch Maree Group.
|
An Ard
|
Representative of the Ard Gneisses, the only known Palaeoproterozoic granites to intrude the Loch Maree Group.
|
Loch Braigh Horrisdale to Sidhean Mòr
|
Representative of the Laxfordian Gairloch Shear Zone, and an exceptional locality for the demonstration of the sequence of Palaeoproterozoic metamorphic events in the Southern Region of the Lewisian Gneiss Complex.
|
Alligin (Diabaig)
|
Representative of the transition from Scourian gneisses of the Central Region to those affected by Inverian and Laxfordian reworking to the south. Exceptional examples of Laxfordian ductile shear-zones.
|
Torridonian Block — Chapter 4
|
|
Stoer
|
Representative of the internationally important Stoer Group, the only unmetamorphosed Mesoproterozoic stratigraphical group in Britain, and an exceptional example of a sedimentary and volcanic sequence formed in a rift environment.
|
Loch na Dal
|
Representative of the lower part of the Sleat Group.
|
Kylerhea Glen
|
Representative of the middle to upper part of the Sleat Group.
|
Loch Eishort
|
Representative of the upper part of the Sleat Group.
|
Diabaig
|
Representative of the Diabaig Formation of the Torridon Group and of the Torridonian/Lewisian unconformity. Exceptional locality for demonstrating the progressive burial of an exhumed Precambrian topography by river sands and lake silts accumulating in a Neoproterozoic rift-valley. Exceptional examples of microfossils in the lake silts that deserve further research.
|
Upper Loch Torridon
|
Representative of the Diabaig Formation of the Torridon Group and of the Torridonian/Lewisian unconformity. Exceptional locality for demonstrating the progressive burial of an exhumed Precambrian topography by river sands and lake silts accumulating in a Neoproterozoic rift-valley.
|
Rubha Dunan Enard Bay
|
Representative of the unconformities between the Stoer and Torridon groups, and between the Lewisian gneisses and the Stoer Group.
Exceptional as the only locality at which the unconformable relationship between the Mesoproterozoic Stoer Group and the Neoproterozoic Torridon Group can be proved unequivocally. Also representative of the unconformity between the Lewisian gneisses and the Stoer Group.
|
Achduart
|
Representative of the basal members of the Applecross Formation of the Torridon Group.
|
Aultbea
|
Representative of the Aultbea Formation of the Torridon Group.
|
Cailleach Head
|
Representative of the Cailleach Head Formation of the Torridon Group. Exceptional example of a Precambrian cyclothemic sequence.
|
Moine Block
|
|
The Moine Thrust Belt Network — Chapter 5
|
|
Eriboll
|
Representative of the northern part of the Moine Thrust Belt. Exceptional examples of thrust structures, associated folds, and mylonites. Internationally important for historical reasons, as a key locality for the understanding of concepts of compressional tectonics.
|
Cleit an t-Seabhaig
|
Representative of mylonitic rocks from the uppermost part of the Moine Thrust Belt and the lowermost part of the Moine Thrust Sheet. Internationally important as the location at which the structure considered to be the Moine Thrust was first directly observed.
|
Faraid Head
|
Representative of mylonitic rocks from the uppermost part of the Moine Thrust Belt and the lowermost part of the Moine Thrust Sheet. Exceptional example of a klippe of the Moine Thrust Sheet. Internationally important as one of the first localities where the kilometre-scale displacement of a major thrust sheet was recognized.
|
Sango Bay
|
Exceptional examples of post-Caledonian normal faults that have downthrown Moine Thrust Belt mylonites of the Faraid Head klippe.
|
Foinaven
|
Exceptional examples of thrust structures, including classic examples of a duplex, within Cambrian quartzites of the Moine Thrust Belt.
|
Glencoul
|
Representative of the northern part of the Assynt Culmination in the Moine Thrust Belt. Exceptional examples of thrust exposures. Internationally important as a world-famous view of large-scale thrust sheets.
|
Skiag Bridge
|
Representative of the foreland succession, Sole Thrust, and lowest imbricate systems in the Assynt Culmination. Exceptional examples of stratigraphical repetition due to thrusting. Internationally important as a teaching site for basic thrust concepts.
|
Stronchrubie Cliff
|
Representative of imbricate thrusts within the Sole Thrust Sheet in the Assynt Culmination. Exceptional examples of sections that can be used to study the three-dimensional geometry of an imbricate system.
|
Traligill Burn
|
Representative of thrusting within the Sole Thrust Sheet in the Assynt Culmination. Exceptional exposures of a thrust plane.
|
Ben More Assynt–Conival–Na Tuadhan
|
Representative of the central part of the Assynt Culmination, including the Ben More Thrust. Exceptional large-scale exposures of thrusts and related folds. Internationally important as a classic location for the demonstration of thrust structures.
|
Sgonnan Mòr–Dubh Loch Beag–Upper Glen Oykel
|
Representative of the Ben More Thrust and associated fold and thrust structures in the Assynt Culmination. Also representative of the relationships between Lewisian and Torridonian units in the Ben More Thrust Sheet.
|
Cam Loch
|
Representative of thrust klippen and thrust-propagation folding in the Assynt Culmination.
|
Knockan Crag
|
Representative of the Moine Thrust and of the Moine mylonites. Exceptional example of a well-exposed, accessible thrust plane. Internationally important as one of the first locations at which the Moine Thrust was observed and as a world-famous locality for the study of thrust structures.
|
Dundonnell
|
Representative locality at which a 'piggy-back' thrust sequence was first demonstrated in the Moine Thrust Belt. Exceptional and internationally important as the type example of an antiformal-stack duplex.
|
Càrn na Canaich
|
Representative of those parts of the Moine Thrust Belt that show little or no deformation in the footwall to the Moine Thrust.
|
Slioch–Heights of Kinlochewe
|
Representative of the Moine Thrust Belt and the foreland succession in the Kinlochewe area. Of historical importance as one of the key localities of the 'Highlands Controversy'.
|
Meall a' Ghiubhais
|
Exceptional views of major thrust sheets and klippen in the Moine Thrust Belt, including the Kishorn Thrust Sheet.
|
Beinn Liath Mhor
|
Representative of the Moine Thrust Belt in the Achnashellach area. Exceptional examples of large-scale imbricate systems that can be clearly seen from distant viewpoints.
|
Cnoc nam Broc, Kishorn
|
Representative of a major fold–thrust complex termed the 'Kishorn Thrust Sheet', one of the major structures of the southern Moine Thrust Belt.
|
Slumbay Island, Loch Carron
|
Exceptional examples of mylonites in the Moine Thrust Belt.
|
Carn a' Bhealaich Mhoir
|
Representative of the Lewisianaorridonian unconformity within the Moine Thrust Belt.
|
Hangman's Bridge
|
Representative of the Moine Thrust, being one of the few localities where the thrust plane is actually exposed.
|
Ard Hill
|
Representative of the Balmacara Thrust and associated structures of the Moine Thrust Belt in the Lochalsh area.
|
Ord
|
Representative of the Ord Window, one of the major structures in the Moine Thrust Belt whose origin is not yet fully understood.
|
Tarskavaig
|
Representative of the Tarskavaig thrust sheets, and the metasedimentary rocks of the enigmatic Tarskavaig Group.
|
Ard Thurinish–Port na Long
|
Representative of the Moine Thrust, being its southernmost exposure.
|
Moine (North) Network — Chapter 6
|
|
Ben Hutig
|
Representative of the lower parts of the Moine Supergroup.
Exceptional examples of deformed pebbles and quartz veins that have been used to study deformation mechanisms.
|
Port Vasgo–Strathan Bay
|
Representative of the basal Moine metasedimentary rocks, including conglomerate units, the underlying Lewisianoid basement, and the
Talmine Imbricate Zone. Exceptional examples of outcrop-scale sedimentary and tectonic structures that have been used to interpret the regional structural history.
|
Melness
|
Representative of the basal Moine metasedimentary rocks and the underlying Lewisianoid basement, and of the Talmine Imbricate Zone.
|
Allt na Caillich
|
Representative of the Ben Hope Thrust and Ben Hope Sill. Exceptional example of an intra-Moine thrust.
|
Allt an Dherue
|
Representative of the basal Moine metasedimentary rocks and the underlying Lewisianoid basement. Representative of the Loch a' Mhoid Metadolerite Suite.
|
Coldbackie Bay
|
Representative of the unconformity between the Moine psammites and the overlying sandstones and conglomerates, which are probably Devonian in age.
|
Strathan Skerray to Skerray Bay
|
Representative of the Borgie Lewisianoid Inlier.
|
Aird Torrisdale
|
Representative of the Naver Thrust Zone. Exceptional exposures of ductile thrust contacts between Moine rocks and Lewisianoid gneisses and within the Moine sequence.
|
Ard Mor (Bettyhill)
|
Representative of the migmatitic Moine rocks of the Bettyhill Banded Formation, and of the amphibolite intrusions of the Bettyhill Suite.
|
Farr Bay (Bettyhill)
|
Representative of the Farr Lewisianoid inlier and associated Moine rocks of the Bettyhill Banded Formation. Exceptional examples of refolded folds.
|
Glaisgeo to Farr Point
|
Representative of the appinitic, dioritic and amphibolitic Clerkhill Intrusion, and the Moine rocks of the Bettyhill Banded Formation.
|
Sgeir Ruadh (Portskerra)
|
Representative of the migmatitic Moine rocks known as the Portskerra gneisses, and their relationships with mafic intrusions of the Bettyhill Suite and with the Strath Halladale Granite Complex. Also shows the unconformity between the Moine rocks and the overlying Middle Devonian sandstones.
|
Dirlot Castle
|
Representative of the unconformity between the Moine rocks and the overlying Devonian carbonate-cemented breccias and sandstones.
|
Ben Klibreck
|
Representative of the Naver Thrust. Exceptional examples of migmatites, first studied in the 1920s and still the subject of research.
|
Oykel Bridge
|
Exceptional examples of mullions in the Moine rocks. Historically important in the development of ideas relating small-scale structures to regional tectonics.
|
The Airde of Shin
|
Representative of the lithologically diverse Shin Lewisianoid Inlier, which includes amphibolitic and quartzofeldspathic gneisses, metalimestones and schistose calc-silicate rocks.
|
Allt Doir' a' Chatha
|
Representative of finely banded amphibolitic rocks of the Shin Lewisianoid Inlier, originally interpreted as metavolcanic units within the Moine.
|
Creag na Croiche
|
Representative of the outer contact and the migmatitic envelope of the Rogart Pluton.
|
Aberscross Burn-Kinnauld
|
Representative of the transition from unmigmatized Moine rocks into the migmatitic envelope of the Rogart Pluton.
|
Brora Gorge
|
Representative of the outer contact and the migmatitic envelope of the Rogart Pluton.
|
Carn Gorm
|
Representative of the Carn Gorm 'Knoydartian' pegmatite, which has been dated by Rb-Sr methods and provides evidence for a Precambrian metamorphic event affecting the Moine rocks.
|
Comrie
|
Representative of Neoproterozoic-age mafic meta-igneous rocks in the Moine succession.
|
Cromarty and Rosemarkie Inners
|
Representative of the Moine and Lewisianoid rocks of the Cromarty and Rosemarkie inliers within the Devonian basins of the Moray Firth.
|
Moine (Central) Network — Chapter 7
|
|
Fannich
|
Representative of the Morar and Glenfinnan groups, together with associated Lewisianoid inliers. Also representative of the ductile Sgurr Beag Thrust, which separates the two groups.
|
Mean an t-Sithe and Creag Rainich
|
Representative of the Sgurr Beag Thrust, demonstrating the chronological relationships between the period of ductile thrusting within the Moine Supergroup and the later movement focused on the Moine Thrust Belt.
|
Loch Monar
|
Representative of the Glenfinnan Group. Exceptional examples of fold interference patterns. Internationally important for the study of the geometry and formation mechanisms of complex fold structures in metasedimentary rocks.
|
Abhainn Gleann nam Fiadh
|
Representative of the Glenfinnan Group. Exceptional examples of well-preserved sedimentary structures, including cross-bedding and slump structures.
|
Attadale
|
Representative of the unconformity between the Moine rocks and the underlying Lewisianoid basement. Exceptional example of the basal conglomerate of the Moine succession.
|
Dornie-Inverinate Road Section
|
Representative cross-section across the Glenelg–Attadale Lewisianoid Inlier, including quartzofeldspathic gneisses, ultramafic bodies, metasedimentary rocks and eclogites, and also the zone of deformation separating the eastern and western parts of the inlier.
|
Avernish
|
Representative of the Glenelg–Attadale Lewisianoid Inlier, showing the original unconformable relationship between the inlier and the overlying Moine rocks.
|
Totaig
|
Representative of the variety of rocks in the eastern part of the Glenelg–Attadale Lewisianoid hiller, including metalimestones, kyanite-bearing gneisses, eulysite, graphitic schists, and exceptional examples of eclogites.
|
Allt Cracaig Coast
|
Representative of the Glenelg–Attadale Lewisianoid Inlier, showing the original unconformable relationship between the inlier and the Moine rocks. Exceptional example of the tectonized basal conglomerate of the Moine succession.
|
Druim Iosal
|
Representative of the variety of rocks in the eastern part of the Glenelg–Attadale Lewisianoid Inlier, including metalimestones, calc-silicate rocks, graphitic schists and exceptional examples of kyanite-bearing pelitic gneisses.
|
Beinn a' Chapuill
|
Representative of the Glenelg–Attadale Lewisianoid Inlier, showing the relationships between the inlier and the overlying Moine rocks. Exceptional example of a kilometre-scale refolded fold.
|
Eilean Chlaraail-Camas nan Ceann
|
Representative of the western part of the Glenelg–Attadale Lewisianoid Inlier.
|
Rubha Camas na Cailinn
|
Representative of the Glenelg–Attadale Lewisianoid Inlier, and showing Moine rocks interleaved and folded together with rocks of the inlier.
|
Ard Ghunel
|
Exceptional examples of zoned ultramafic pods within the Lewisianoid gneisses of the Moine Nappe.
|
Moine (South) Network — Chapter 8
|
|
Glen Doe
|
Representative of metagabbroic intrusive rocks associated with the West Highland Granite Gneiss Suite.
|
Kinloch Hourn
|
Representative of the Sgurr Beag Thrust, an exceptional example of a major ductile thrust within the Moine succession.
|
Quoich Spillway
|
Representative of the West Highland Granite Gneiss Suite.
|
Knoydart Mica Mine
|
Representative of the 'Knoydartian' pegmatite suite, dating of which provides evidence for a Precambrian metamorphic event affecting the Moine rocks. Exceptional examples of large mica and beryl crystals.
|
North Morar
|
Representative of the Morar Group of the Moine and of associated Lewisianoid inliers. Also representative of the change from low-grade, moderately deformed Moine rocks in the west, to higher-grade, complex thrust and folded Moine rocks in the east.
|
Drulmindarroch
|
Representative of the Lower Morar Psammite Formation.
|
Fassfern to Lochailort Road Cuttings
|
Representative section across the whole Moine Supergroup in Inverness-shire.
|
Lochailort
|
Representative of the southern outcrop of the Sgurr Beag Thrust.
|
Eas Chia-Aig Waterfalls
|
Representative of an inlier of migmatitic gneisses correlated with the Glenfinnan Group, lying within the Loch Ed Group of the Moine.
|
Loch Moidart Road Cuttings
|
Representative of the Upper Morar Psammite Formation, showing good examples of sedimentary structures such as cross-bedding and slumps.
|
Eilean Mòr and Camas Choire Mhuilinn
|
Representative of the Upper Morar Psammite Formation. Exceptional examples of sedimentary structures such as cross-bedding and de-watering structures.
|
Ardalanish Bay, Mull
|
Representative of the most westerly known outcrop of the Moine succession and its contact with the late Caledonian Ross of Mull Pluton. Exceptional examples of aluminosilicate minerals within the metamorphic aureole.
|
Lewisian and Moine of Shetland Network — Chapter 9
|
|
Uyea to North Roe Coast
|
Representative of the Caledonian Front in Shetland, including rocks correlated with the Lewisian gneisses, and the Moine and Dalradian supergroups. Internationally important for correlation along the length of the Caledonide Belt.
|
Gutcher
|
Representative of psammites and microcline augen gneisses of the Yell Sound Division, which is considered to correlate with the Moine Supergroup.
|
North Sandwick
|
Representative of psammites, pelites and quartzites of the Yell Sound Division, which is considered to correlate with the Moine Supergroup, and also of metamorphosed mafic sheets intruding the metasedimentary rocks.
|
Hascosay
|
Representative of the mylonitic gneisses of the Hascosay Slide Zone.
|
Calliyoe
|
Representative of the mylonitic gneisses of the Hascosay Slide Zone. Exceptional examples of fold structures within the mylonitic rocks.
|
Voxter Voe and Valayre Quarry
|
Representative of the Valayre Gneiss, a microcline-megacryst augen gneiss that forms the western edge of the Boundary Zone between the Moine and Dalradian rocks of Shetland.
|
Name of swarm/ sub-suite/suite
|
Age
|
Area of occurrence
|
Abundance
|
Rock types
|
Quartzose Amphibolite
|
Upper Ordovician
|
Near Fort Augustus.
|
Local
|
Quartzose
amphibolite, tonalite
|
Glen Moriston Vein-Complex
|
Upper Ordovician
|
In Glen Moriston, extending north to Strathglass.
|
Abundant
|
Muscovite-biotite granite, aplitic and pegmatitic granite
|
Loch Eil Granite Vein-Complex
|
Late Silurian
|
West end of Loch Eil, Glen Fionnlighe.
|
Abundant
|
Granite, including aplitic and pegmatitic granite
|
Loch Arkaig Granite Vein- Complex
|
Late Silurian
|
Centred on Meall Blair north of Loch Arkaig.
|
Abundant
|
Granite, including aplitic and pegmatitic granite
|
Mallie Granite Vein-Complex
|
Late Silurian
|
In Glen Mallie, south of Loch Arkaig.
|
Abundant
|
Granite, including aplitic and pegmatitic granite. Includes small granodiorite body
|
porphyritic microgranodiorite ('Felsic Porphyrites')
|
Late Silurian
|
Cluanie area, upper Glen Moriston.
|
Moderately abundant
|
Porphyritic
microgranodiorite
|
Microdiorite Sub-suite
|
Late Silurian
|
Widespread across Moine outcrop south of Glen Moriston to the Sound of Mull. Also present in Ross-shire.
|
Very abundant, reaching maximum concentration in central zone between Cluanie and Salen
|
Range from
microgranodiorite to melamicrodiorite
|
Appinite Suite
|
Late Silurian
|
Widespread across the Moine outcrop but concentrated in Strontian-Sunart-Moidart area and in Glen Garry. Associated with the Strontian Pluton. Sparse to north of Glen Affric and Glen Shiel.
|
Abundant within clusters
|
Mainly coarse-grained hornblende-diorite but range from monzonite to pyroxene- and olivine-bearing hornblende-rich ultramafic rocks
|
porphyritic microgranodiorite ('Main Felsic Porphyrites')
|
Late Silurian
|
From Glen Affric south-west via Cluanie, Loch Arkaig and Loch Shiel down to Loch Mine on the Sound of Mull.
|
Abundant
|
Porphyritic microgranodiorite ranging to quartz microdiorites
|
Banavie Vein-Complex
|
Late Silurian
|
Adjacent to the Great Glen south of Loch Lochy. Extends up to 5 km north-west of Great Glen Fault.
|
Abundant
|
Granite and subsidiary aplitic granite and quartz feldspar pegmatite veins
|
Glen Garry Vein-Complex
|
Late Silurian
|
From Cluanie south-east to Loch Lochy, centred on Glen Garry.
|
Abundant
|
Mostly medium- to coarse-grained granodiorite, but ranging from quartz diorite to monzogranite
|
microgranite swarm ('felsites)
|
Early Devonian
|
Widespread but only abundant in swarm east of Ratagain Pluton.
|
Not abundant except in Ratagain swarm
|
Microgranite and microgranodiorite, locally porphyritic
|
Lamprophyre Sub-suite
|
Early Devonian
|
Widespread but concentrated in Ratagain swarm stretching from Loch Hourn north-east through Kintail to Glen Affric and Glen Cannich. Dykes extend west of Moine Thrust on Skye and in Applecross area.
|
Not abundant except in Ratagain swarm
|
Pyroxene minette, but some vogesite and rare kersantite
|
camptonite-monchiquite suite
|
Permo- Carboniferous
|
Widespread but concentrated in swarms — Monar, Killilan, Morar, Eil-Arkaig, Ardgour and Iona- Ross of Mull.
|
Locally abundant
|
Camptonite and camptonitic basalt mainly, rare monchiquite
|
Palaeogene dykes, mainly of the Skye, Mull, and Ardnamurchan swarms
|
Palaeocene to Early Eocene
|
Widespead on Sleat and west coast south of Loch Nevis.
|
Locally abundant
|
Dolerite, basalt
|
Nature and trend of intrusion
|
Thickness of intrusion
|
Deformation
|
Reference
|
Elliptical masses, elongated north-east, rarely dykes. Found within Fort Augustus Granite Gneiss.
|
Bodies up to 1 km long but also as smaller pods. Rare dykes c. 3 m thick.
|
Low.
|
May and Highton, 1997
|
Lenticular sheets, veins, mainly concordant. Thicker sheets trend north-east.
|
From a few cm up to 40 m thick, but typically < 2 m thick.
|
Foliated, folded, boudined.
|
May and Highton, 1997
|
Ramifying network, no preferred orientation.
|
Seldom > 2 m thick, rarely larger bodies.
|
Only minor deformation.
|
Fettes and Macdonald, 1978
|
Ramifying network, no preferred orientation.
|
Seldom > 2 m thick, rarely larger bodies.
|
Only minor deformation.
|
Fettes and Macdonald, 1978
|
Ramifying network, no preferred orientation.
|
Seldom > 2 m thick, rarely larger bodies.
|
Only minor deformation.
|
Fettes and Macdonald, 1978
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Dykes and sheets, trending approximately east. Some irregular bodies.
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Typically c. 2 m thick but up to 5 m recorded.
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Weakly schistose and recrystallized.
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Peacock et al., 1992; May and Highton, 1997
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Sheets and dykes with chilled margins. Mineral assemblages altered and in part recrystallized under greenschist- or epidote-amphibolite-facies conditions. Some irregular sheets in west coastal area exhibit largely unmodified igneous textures and mineralogies. Most sheets dip moderately south-east, but swarms of NNE- and E-W-trending sheets can be distinguished locally.
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Up to 10 m thick but typically c. 1 m thick. Variable thickness along length of intrusion.
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In parts show flow foliation in chilled zones. Locally cleaved, both in marginal zones and throughout whole intrusion.
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Smith, 1979; May and Highton, 1997; Peacock et al., 1993; May et at., 1992
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Small bosses and pods. Also thick sheets.
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Bosses typically 20 m to 50 m across. Sheets mainly in range 2 m to 10 m across.
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Foliated in part, particularly at margins.
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Smith, 1979; May and Highton, 1997
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Dykes and sheets, mainly dipping moderately to the south-east and steeply to north-west.
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Dykes typically < 1 m thick, sheets commonly around 5 m thick , but up to 15 m.
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Oblique internal schistosity common. Recrystallized to greenschist.
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Smith, 1979; Peacock et al., 1992; May and Highton, 1997
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Veins and vein networks. No obvious preferred orientation.
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Typically up to 1 m in width but locally thicker.
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Not foliated.
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Johnstone and Mykura, 1989
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Discrete veins, sheets and larger bodies, which show a general north-east alignment.
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Veins from a few centimetres up to tens of metres thick. Larger masses up to several hundred metres across.
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Not foliated.
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Fettes and Macdonald, 1978
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Dykes commonly aligned east-west.
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1 m to 10 m wide (average 4 m) in Kintail swarm.
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Not foliated.
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May et al., 1992
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Dykes with chilled margins. Commonly altered mineralogy.
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Range from 0.2 m to 6 m. Average thickness c. 3 m.
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Not foliated.
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Smith, 1979
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Dykes with chilled margins. Dykes subvertical. Trend east-west in north and ENE in Ardgour swarm and south-east in Ross of Mull.
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Average thickness c. 1 m.
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Not foliated.
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Rock, 1983
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Dykes with chilled margins, commonly vesicular.
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Commonly 0.3 m to 2 m thick but averages 4.5 m in Morar and can be 10 m or more.
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Not foliated.
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Speight et at, 1982
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