Mineral Reconnaissance Programme Report
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Natural Environment Research Council Institute of Geological Sciences Mineral Reconnaissance Programme Report -4 A report prepared for the Department of Industry This report relates to work carried out by the Institute of Geological Sciences on behalf of the Department of industry. The information contained herein must not be published without reference to the Director, Institute of Geological Sciences D. Ostle Programme Manager Institute of Geological Sciences Keyworth, Nottingham NG12 5GG No. 50 Geochemical drainage survey of central Argyll, Scotland INSTITUTE OF GEOLOGICAL SCIENCES Natural Environment Research Council Mineral Reconnaissance Programme Report No. 50 Geochemical drainage survey of I central Argyll, Scotland J. S. Coats, BSc, PhD 8. C. Tandy, MSc U. Mel. Michie, BSc 0 Crown copyright 7982 London 1982 A report prepared for the Department of Industry Mineral Reconnaissance Programme Reports 30 Porphyry style copper mineralisation at Black Stockarton Moorsouth-west Scotland I 1 The concealed granite roof in south-west Cornwall 31 Geophysical investigations in the 2 Geochemical and geophysical investigations around Closehouse-Lunedale area Garras Mine, near Truro, Cornwall 32 Investigations at Polyphant, near Launceston, . 3 Molybdenite mineralisation in Precambrian rocks Cornwall near Lairg, Scotland 33 Mineral investigations at Carrock Fell, Cumbria. Part 4 Investigation of copper mineralisation at Vidlin, 1 -Geophysical survey I Shetland 34 Results of a gravity survey of the south-west margin 5 Preliminary mineral reconnaissance of Central Wales of Dartmoor, Devon 6 Report on geophysical surveys at Struy, Inverness- 35 Geophysical investigation of chromite-bearing shire ultrabasic rocks in the Baltasound-Hagdale area, I Unst, Shetland Islands 7 Investigation of tungsten and other mineralisation associated with the Skiddaw Granite near Carrock 36 An appraisal of the VLF ground resistivity technique Mine, Cumbria as an aid to mineral exploration 1 8 Investigation of stratiform sulphide mineralisation in 37 Compilation of stratabound mineralisation in the parts of central Perthshire Scottish Caledonides 9 Investigation of disseminated copper mineralisation 38 Geophysical evidence for a concealed eastern I near Kilmelford, Argyllshire, Scotland extension of the Tanygrisiau microgranite and its possible relationship to mineralisation 10 Geophysical surveys around Talnotry mine, Kirkcudbrightshire, Scotland 39 Copper-bearing intrusive rocks at Cairngarroch Bay, south-west Scotland I 11 A study of the space form of the Cornubian granite batholith and its application to detailed gravity 40 Stratabound barium-zinc mineralisation in Dalradian surveys in Cornwall schist near Aberfeldy, Scotland: Final report 12 Mineral investigations in the Teign Valley, Devon. 41 Metalliferous mineralisation near Lutton, Ivybridge, Part 1--8arytes Devon 13 Investigation of stratiform sulphide mineralisation at 42 Mineral exploration in the area around Culvennan McPhun’s Cairn, Argyllshire Fell, Kirkcowan, south-western Scotland I 14 Mineral investigations at Woodhall and Longlands in 43 Disseminated copper-molybdenum mineralisation north Cumbria near Ballachulish, Highland Region 15 Investigation of stratiform sulphide mineralisation at 44 Reconnaissance geochemical maps of parts of south I Meall Mor, South Knapdale, Argyll Devon and Cornwall 16 Report on geophysical and geological surveys at 45 Mineral investigatons near Bodmin, Cornwall. Part Blackmount, Argyllshire 2 New uranium, tin and copper occurrence in the Tremayne area of St Columb Major 17 Lead, zinc and copper mineralisation in basal I Carboniferous rocks at Westwater, south Scotland 46 Gold mineralisation at the southern margin of the Loch Doon granitoid complex, south-west Scotland 18 A mineral reconnaissance survey of the Doon-Glenkens area, south-west Scotland 47 An airborne geophysical survey of the Whin Sill between Haltwhistle and Scats’ Gap, south I 19 A reconnaissance geochemical drainage survey of Northumberland the Criffel-Dalbeattie granodiorite complex and its environs 48 Mineral investigations near Bodmin, Cornwall. Part 3 The Mulberry and Wheal Prosper area I 20 Geophysical field techniques for mineral exploration 49 Seismic and gravity surveys over the concealed 21 A geochemical drainage survey of the Fleet granitic granite ridge at Bosworgy, Cornwall complex and its environs 50 Geochemical drainage survey of central Argyll, 22 Geochemical and geophysical investigations north- I Scotland west of Llanrwst, North Wales 23 Disseminated sulphide mineralisation at Garbh I Achadh, Argyllshire, Scotland 24 Geophysical investigations along parts of the Dent and Augill Faults The Institute of Geological Sciences was formed by the incorporation of the Geological Survey of Great Britain and 25 Mineral investigations near Bodmin, Cornwall. Part the Geological Museum with Overseas Geological Surveys I 1 -Airborne and ground geophysical surveys and is a constituent body of the Natural Environment 26 Stratabound barium-zinc mineralisation in Dalradian Research Council schist near Aberfeldy, Scotland: Preliminary report 27 Airborne geophysical survey of part of Anglesey, Bibliographical reference North Wales Coats, J. S. and others. 1982. Geochemical drainage 28 A mineral reconnaissance survey of the survey of central Argyll, Scotland. Mineral 1 Abington-Biggar-Moffat area, south-central Reconnaissance Programme Rep. Inst. Geol. Sci., No. 50 Scotland 29 Mineral exploration in the Harlech Dome, North Photocopied in England for the Institute of Geological I Wales Sciences by Four Point Printing I CONTENTS 12 Greyscale map of lead in panned concen- trates 14 Summary 1 13 Zinc in stream sediments in pocket 14 Zinc in panned concentrates in pocket Introduction 1 15 Greyscale map of zinc in stream sedi- General geology 3 ments 16 16 Greyscale map of zinc in panned concen- Mineralisation 3 trates 17 Regional reconnaissance survey 4 17 Nickel in stream sediments in pocket Introduction 4 18 Nickel in panned concentrates in pocket Analytical methods 4 19 Greyscale map of nickel in stream sedi- Statistical analysis 6 ments 18 20 Greyscale map of nickel in panned concen- Regional geochemical variation of elements 9 trates 19 Greyscale maps 9 21 Barium in panned concentrates in pocket Copper 9 22 Greyscale map of barium in panned concen- Lead 12 trates 21 Zinc 15 23 Greyscale map of uranium in stream sedi- Nickel 15 ments 22 Cobalt 20 24 Greyscale map of molybdenum in stream Barium _20 sediments 24 Uranium 20 25 Greyscale map of antimony in panned Molybdenum 23 concentrates 25 Silver 23 26 Greyscale map of tin in panned concen- Antimony 23 trates 27 Tin 26 27 Greyscale map of iron in panned concen- Iron 26 trates 28 Cerium 26 28 Greyscale map of cerium in panned concen- Calcium 31 trates 29 Manganese 3 1 29 Greyscale map of calcium in panned concen- Titanium 3 1 trates 30 Detailed drainage surveys 3 1 30 Greyscale map of manganese in panned Introduction 3 1 concentrates 3 2 Tyndrum-Glen Fyne fault system 34 31 Greyscale map of titanium in panned Garabal Hill-Glen Fyne igneous complex 40 concentrates 3 3 Ardrishaig Phyllites 43 32 Anomalies in Upper Glen Fyne 36 Pyrite Zone 45 33 Anomalies at Invercorachan 38 Loch Tay Limestone 48 34 Anomalies in Lower Glen Fyne 39 Green Beds 51 35 Anomalies near Loch Sloy 42 36 Anomalies at Cruach Mhor and Strathlachlan Conclusions 5 2 River 47 Recommendations 54 37 Anomalies at Lephinmore 49 38a Anomalies at Lephinchapel 50 Acknowledgements 54 38b Anomalies at Evanachan 50 References 54 TABLES FIGURES 1 Summary statistics of reconnaissance drain- Central Argyll - location and geology 2 age samples 6 Central Argyll- mineral localities 5 2 Class intervals for drainage samples 7 Location of stream sediment sites in pocket 3 Correlation coefficients between elements Location of panned concentrate sites in pocket determined in drainage samples 8 Copper in stream sediments in pocket 4 Class intervals and percentile limits for Copper in panned concentrates in pocket greyscale isopleth maps 8 Greyscale map of copper in stream sedi- ments 10 8 Greyscale map of copper in panned concen- trates 11 9 Lead in stream sediments in pocket 10 Lead in panned concentrates in pocket 11 Greyscale map of lead in stream sedi- ments 13 SUMMARY 50 km north-west of Glasgow. It extends along the north-east to south-west Caledonian strike of the A reconnaissance geochemical drainage survey of Middle and Upper Dalradian rocks from Tyndrum 720 km2 of Dalradian outcrop in central Argyll to Ardrishaig, and covers a total area of about identified base-metal anomalies in the Pyrite Zone, 720 km2. Ardrishaig Phyllites, Loch Tay Limestone and the Access to the area is by the A82 and A83 trunk Green Beds. Faulting and igneous intrusion roads from Glasgow, and by the Glasgow to Oban modified the distribution of metal content within and Fort William railway line. Limited access by these formations. In the results of the reconnaiss- sea is provided by Loch Fyne to the south, and the ance survey, copper reached maxima of 170 ppm Crinan Canal to the west. and 1454 ppm in stream sediments and panned The physiographical features are controlled by concentrates respectively; lead 1050 ppm and the north-east trending Caledonian grain, modified 2595 ppm; zinc 2500 ppm and 1114 ppm; and in parts by glacial effects. The highest ground is nickel 190 ppm and 998 ppm. Maximum contents located in the north-east where it attains a height of cobalt, uranium and molybdenum in stream of 1130 m on Ben Lui.