Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-23T08:09:53.517Z Has data issue: false hasContentIssue false
  • English
  • Français

Field and isotopic evidence for a c. 750 Ma tectonothermal event in Moine rocks in the Central Highland region of the Scottish Caledonides

Published online by Cambridge University Press:  03 November 2011

M. A. J. Piasecki  and
O. van Breemen
M. A. J. Piasecki
Affiliation:
Department of Geology, University of Hull, Cottingham Road, Hull HU6 7RX, England.
O. van Breemen
Affiliation:
Geological Survey of Canada, 601 Booth Street, Ottawa K1A 0E8, Canada.
Get access Rights & Permissions [Opens in a new window]

Abstract

Evidence is presented for a late Proterozoic, tectonothermal event which affected the rocks of the Moine assemblage in the Central Highland region of the Scottish Caledonides c. 750 Ma ago. This is about 200 Ma before the early Palaeozoic Grampian orogeny, whose effects are superimposed on the Moine rocks as well as dominating the tectonism in the Dalradian Supergroup.

Field and isotopic studies are integrated in zones of ductile thrusting (sliding) which are typified by belts of tectonic schists with related swarms of quartz and muscovite-bearing pegmatite veins. Of particular significance is a ductile thrust (the Grampian slide) which separates deeper crustal rocks (the Central Highland division), interpreted as showing the imprint of the Grenville orogeny, from shallower rocks (the Grampian division) representing a supracrustal assemblage formed between the Grenville and the c. 750 Ma events.

The Grampian slide is the structurally highest member of a system of related, previously unrecorded slides affecting the Central Highland division. New structural, petrographic and Rb-Sr isotopic data, obtained largely from a recently recognised inlier of the Central Highland division at Laggan, bear out that the quartz and pegmatite veins are segregations formed during ductile shearing under amphibolite facies conditions. Muscovites from these veins yield ages between 780 and 730 Ma, and a regression analysis of tectonic schists and the muscovites gives an age of 740 ± 40 Ma. These data substantiate our previous hypothesis that the deeper-seated Moine rocks were affected by a distinct orogenic event at 750 ± 30 Ma.

In the Northern Highlands, similar vein swarms are related to the Sgurr Beag slide and to belts of previously unrecorded tectonic schists in the Glenfinnan division of the Moine assemblage. A new, 755 ± 8 Ma age obtained from such a tectonic schist at Kinloch Hourn, combined with previous, similar age data from lensoid pegmatites, imply that the c. 750 Ma event may have also affected the Morar and Glenfinnan divisions.

Keywords

basementcoverGrampianGrenvilleisochronmuscoviteNorthern HighlandsorogenypegmatiteRb–Sr ageslidetectonic schistwhole-rock.
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 73 , Issue 3 , 1983 , pp. 119 - 134
Copyright
Copyright © Royal Society of Edinburgh 1983

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Aftalion, M. & van Breemen, O. 1980. U-Pb zircon, monazite and Rb–Sr whole rock systematics of granitic gneiss and psammitic to semi-pelitic host gneiss from Glenfinnan, north-western Scotland. CONTRIB MINERAL PETROL 72, 87–98.CrossRefGoogle Scholar
Anderson, J. G. C. 1956. The Moinian and Dalradian rocks between Glen Roy and the Monadhliath Mountains, Inverness-shire. TRANS R SOC EDINBURGH 63, 15–36.CrossRefGoogle Scholar
Beach, A. 1981. Some observations on the development of thrust faults in the Ultradauphinois Zone, French Alps. In McClay, K. R. & Price, N. J. (eds) Thrust and Nappe Tectonics, 329–34. SPEC PUBL GEOL SOC LONDON 9.Google Scholar
Bowes, D. R. 1968. The absolute time scale and the subdivision of Precambrian rocks in Scotland. GEOL FOREN FORH STOCKHOLM 90, 175–88.CrossRefGoogle Scholar
Bowes, D. R. 1978. Shield formation in early Precambrian times. In Bowes, D. R. & Leake, B. E. (eds) Crustal evolution in northwestern Britain and adjacent regions, 39–80. GEOL J SPEC ISSUE 10.Google Scholar
Bowes, D. R. 1980. The absolute time-scale and the subdivision of Precambrian rocks in northwestern Britain. In Mitrofanov, F. P. (ed.) Principles and criteria of subdivision of Precambrian in mobile zones, 32–54. Leningrad: Nauka.Google Scholar
Bowes, D. R. & Gaál, G. 1981. Precambrian record of the eastern North Atlantic Borderlands. In Kerr, J. W. & Fergusson, A. J. (eds) Geology of the North Atlantic Borderlands, 31–55. MEM CAN SOC PET GEOL 7.Google Scholar
Brewer, M. S., Brook, M. & Powell, D. 1979. Dating of the tectono-metamorphic history of the south-western Moine, Scotland. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles-reviewed, 129–37. SPEC PUBL GEOL SOC LONDON 8.Google Scholar
Brook, M., Brewer, M. S. & Powell, D. 1976. Grenville age for rocks in the Moine of north-western Scotland. NATURE 260, 515–7.CrossRefGoogle Scholar
Brook, M., Powell, D. & Brewer, M. S. 1977. Grenville events in the Moine rocks of the Northern Highlands, Scotland. J GEOL SOC LONDON 133, 489–96.CrossRefGoogle Scholar
Clifford, T. N. 1958. The stratigraphy and structure of part of the Kintail district of southern Ross-shire–its relationship to the Northern Highlands. Q J GEOL SOC LONDON 113, 57–92.CrossRefGoogle Scholar
Dalziel, I. W. D. 1963. Zircons from the Granitic Gneiss of Western Ardgour, Argyll; their bearing on its origin. TRANS GEOL SOC EDINBURGH 19, 349–62.CrossRefGoogle Scholar
Dalziel, I. W. D. 1966. A structural study of the granitic gneiss of western Ardgour, Argyll and Inverness-shire. SCOTT J GEOL 2, 125–52.CrossRefGoogle Scholar
Dewey, J. F. 1982. Plate tectonics and the evolution of the British Isles. J. GEOL SOC LONDON 139, 371–412.CrossRefGoogle Scholar
Dickin, A. P., Moorbath, S. & Welke, H. J. 1981. Isotope, trace element and major element geochemistry of Tertiary igneous rocks, Isle of Arran, Scotland. TRANS R SOC EDINBURGH EARTH SCI 72, 159–70.CrossRefGoogle Scholar
Elliott, D. & Johnson, M. R. W. 1980. Structural evolution in the northern part of the Moine thrust belt, NW Scotland. TRANS R SOC EDINBURGH EARTH SCI 71, 69–96.CrossRefGoogle Scholar
Giletti, B. J., Moorbath, S. & Lambert, R. St J. 1961. A geochronological study of the metamorphic complexes of the Scottish Highlands. Q J GEOL SOC LONDON 117, 233–72.CrossRefGoogle Scholar
Harris, A. L., Baldwin, C. T., Bradbury, H. J., Johnson, H. D. & Smith, R. A. 1978. Ensialic basin sedimentation: the Dalradian Supergroup. In Bowes, D. R. & Leake, B. E. (eds) Crustal evolution in northwestern Britain and adjacent regions, 115–38. GEOL J SPEC ISSUE 10.Google Scholar
Harris, A. L. & Pitcher, W. S. 1975. The Dalradian Supergroup. In Harris, A. L., Shackleton, R. M., Watson, J., Downie, C., Harland, W. B. & Moorbath, S. (eds) A correlation of the Precambrian rocks in British Isles, 52–75. SPEC REP GEOL SOC LONDON 6.Google Scholar
Harry, W. T. 1953. The composite granitic gneiss of Western Ardgour. Q J GEOL SOC LONDON 109, 285–310.CrossRefGoogle Scholar
Haselock, P. J. & Winchester, J. A. 1981. A note on the stratigraphic relationship of the Leven Schist and the Monadhliath Schist in the Central Highlands of Scotland. GEOL J 16, 237–41.CrossRefGoogle Scholar
Haselock, P. J., Winchester, J. A. & Whittles, K. H. 1982. The stratigraphy and structure of the southern Monadhliath Mountains between Loch Killin and Upper Glen Roy. SCOTT. J GEOL 18, 275–90.CrossRefGoogle Scholar
Hickman, A. H. 1975. The stratigraphy of the Late Precambriam metasediments between Glen Roy and Lismore. SCOTT J GEOL 11, 171–42.CrossRefGoogle Scholar
Higgins, M. W. 1971. Cataclastic rocks. PROF PAP U S GEOL SURV 687.Google Scholar
Johnson, M. R. W. & Frost, R. T. C. 1977. Fault and lineament patterns in the southern Highlands of Scotland. GEOL MIJNBOUW 56, 283–94.Google Scholar
Johnson, M. R. W., Sanderson, D. J. & Soper, N. J. 1979. Deformation in the Caledonides of England, Ireland and Scotland. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles–reviewed, 165–86. SPEC PUBL GEOL SOC LONDON 8.Google Scholar
Johnstone, G. S. 1975. The Moine Succession. In Harris, A. L., Shackleton, R. M., Watson, J., Downie, C., Harland, W. B. & Moorbath, S. (eds) A correlation of Precambrian rocks in the British Isles, 30–42. SPEC REP GEOL SOC LONDON 6.Google Scholar
Johnstone, G. S., Smith, D. I. & Harris, A. L. 1969. The Moinian assemblage of Scotland. In Kay, M. (ed.) North Atlantic geology and continental drift, 159–80. MEM AM ASSOC PET GEOL 12.Google Scholar
Kennedy, W. Q. 1946. The Great Glen Fault. Q J GEOL SOC LONDON 102, 41–76.CrossRefGoogle Scholar
Lambert, R. St J. 1969. Isotopie studies relating to the Pre-Cambrian history of the Moinian of Scotland. PROC GEOL SOC LONDON 1652, 243–4.Google Scholar
Lambert, R. St. J. & McKerrow, W. S. 1976. The Grampian Orogeny. SCOTT J GEOL 12, 271–92.CrossRefGoogle Scholar
Lambert, R. St J., Winchester, J. A. & Holland, J. G. 1979. Time, space and intensity relationships of the Precambrian and lower Palaeozoic metamorphisms of the Scottish Highlands. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles–reviewed, 363–67. SPEC PUBL GEOL SOC LONDON 8.Google Scholar
Long, L. E. & Lambert, R. St J. 1963. Rb–Sr isotopie ages from the Moine Series. In Johnson, M. R. W. & Stewart, F. H. (eds) The British Caledonides, 217–47. Edinburgh: Oliver & Boyd.Google Scholar
McClay, K. R. & Coward, M. P. 1981. The Moine Thrust Zone. An overview. In McClay, K. R. & Price, N. J. (eds). Thrust and Nappe Tectonics, 241–60. SPEC PUBL GEOL SOC LONDON 9.Google Scholar
Moorbath, S. 1969. Evidence for the age of deposition of the Torridonian sediments of north-west Scotland. SCOTT J GEOL 5, 154–70.CrossRefGoogle Scholar
Parson, L. M. 1979. The state of strain adjacent to the Great Glen fault. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles–reviewed, 287–9. SPEC PUBL GEOL SOC LONDON 8.Google Scholar
Piasecki, M. A. J. 1980. New light on the Moine rocks of the Central Highlands of Scotland. J GEOL SOC LONDON 137, 41–59.CrossRefGoogle Scholar
Piasecki, M. A. J. & van Breemen, O. 1979a. A Morarian age for the “younger Moines” of Central and Western Scotland. NATURE 278, 734–6.CrossRefGoogle Scholar
Piasecki, M. A. J. & van Breemen, O. 1979b. The “Central Highland Granulites”: cover-basement tectonics in the Moine. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles–reviewed, 139–44. SPEC PUBL GEOL SOC LONDON 8.Google Scholar
Piasecki, M. A. J., van Breemen, O. & Wright, A. E. 1981. Late Precambrian geology of Scotland, England and Wales. In Kerr, J. W. & Fergusson, A. J. (eds) Geology of the North Atlantic Borderlands, 57–94. MEM CAN SOC PET GEOL 7.Google Scholar
Powell, D., Baird, A. W., Charnley, N. R. & Jordan, P. J. 1981. The metamorphic environment of the Sgurr Beag Slide; a major crustal displacement zone in Proterozoic, Moine rocks of Scotland. J GEOL SOC LONDON 135, 661–73.CrossRefGoogle Scholar
Pringle, I. R. 1972. Rb–Sr age determinations on shales associated with the Varanger Ice Age. GEOL MAG 109, 465–72.CrossRefGoogle Scholar
Purdy, J. W. & Jäger, E. 1976. K–Ar ages on rock-forming minerals from the central Alps. MEM INST GEOL MINER UNIV PADOVA 30.Google Scholar
Rast, N. 1958. The tectonics of the Schiehallion complex. Q J GEOL SOC LONDON 114, 25–46.CrossRefGoogle Scholar
Rathbone, P. A. & Harris, A. L. 1979. Basement–cover relationships at Lewisian inliers in the Moine rocks. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles–reviewed, 101–7. SPEC PUBL GEOL SOC LONDON 8.Google Scholar
Roberts, J. L. & Treagus, J. E. 1979. Stratigraphical and structural correlation between the Dalradian rocks of the SW and Central Highlands of Scotland. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles–reviewed, 199–204. SPEC PUBL GEOL SOC LONDON 8.Google Scholar
Smith, T. E. 1968. Tectonics in Upper Strathspey, Inverness-shire, Scotland. SCOTT J GEOL 4, 68–84.CrossRefGoogle Scholar
Soper, N. J. & Barber, A. J. 1979. Proterozoic folds on the Northwest Caledonian Foreland. SCOTT J GEOL 15, 1–11.CrossRefGoogle Scholar
Soper, N. J. & Barber, A. J. 1982. A model for the deep structure of the Moine thrust zone. J GEOL SOC LONDON 139, 127–38.CrossRefGoogle Scholar
Steiger, R. H. & Jäger, E. 1977. Subcommission on geochronology convention on the use of decay constants in geo- and cosmo-chronology. EARTH PLANET SCI LETT 36, 359–62.CrossRefGoogle Scholar
Stewart, A. D. 1969. Torridonian rocks of Scotland reviewed. In Kay, M. (ed.) North Atlantic geology and continental drift, 595–608. MEM AM ASSOC PET GEOL 12.Google Scholar
Stewart, A. D. 1975. “Torridonian” rocks of western Scotland. In Harris, A. L., Shackleton, R. M., Watson, J., Downie, C., Harland, W. B. & Moorbath, S. (eds) A correlation of Precambrian rocks in the British Isles, 43–51. SPEC REP GEOL SOC LONDON 6.Google Scholar
Strachan, R. A. 1982. Tectonic sliding within the Moinian Loch Eil Division near Kinlocheil, W. Inverness-shire. SCOTT J GEOL 18, 187–203.CrossRefGoogle Scholar
Swett, K. 1969. Interpretation of depositional and diagenetic history of Cambro-Ordovician Succession of Northwest Scotland. In Kay, M. (ed.) North Atlantic—geology and continental drift, 630–46. MEM AM ASSOC PET GEOL 12.Google Scholar
Tanner, P. W. G. 1971. The Sgurr Beag Slide–a major tectonic break within the Moinian of the Western Highlands of Scotland. Q J GEOL SOC LONDON 126, 435–63.CrossRefGoogle Scholar
Thomas, P. R. 1979. New evidence for a Central Highland Root Zone. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds) The Caledonides of the British Isles–reviewed, 205–11. SPEC PUBL GEOL LONDON 8.Google Scholar
Thomas, P. R. 1980. The stratigraphy and structure of the Moine rocks N of the Schiehallion complex, Scotland. J GEOL SOC LONDON 137, 469–82.CrossRefGoogle Scholar
Treagus, J. E. 1974. A structural cross-section of the Moine and Dalradian rocks of the Kinlochleven area, Scotland. J GEOL SOC LONDON 130, 525–44.CrossRefGoogle Scholar
Treagus, J. E. & King, G. 1978. A complete Lower Dalradian succession in the Schiehallion district, Central Perthshire. SCOTT J GEOL 14, 157–66.CrossRefGoogle Scholar
van Breemen, O., Halliday, A. N., Johnson, M. R. W. & Bowes, D. R. 1978. Crustal addition in late Precambrian times. In Bowes, D. R. & Leake, B. E. (eds) Crustal evolution in northwestern Britain and adjacent regions, 81–106. GEOL J SPEC ISSUE 10.Google Scholar
van Breemen, O & Piasecki, M. A. J. 1983. The Glen Kyllachy Granite and its bearing on the nature of the Caledonian Orogeny in Scotland. J GEOL SOC LONDON 140, 47–62.CrossRefGoogle Scholar
van Breemen, O., Pidgeon, R. T. & Johnson, M. R. W. 1974. Precambrian and Palaeozoic pegmatites in the Moines of northern Scotland. J GEOL SOC LONDON 130, 493–507.CrossRefGoogle Scholar
Watson, J. 1975. The Lewisian complex. In Harris, A. L., Shackleton, R. M., Watson, J., Downie, C., Harland, W. B. & Moorbath, S. (eds) A correlation of Precambrian rocks in the British Isles, 15–29. SPEC REP GEOL SOC LONDON 6.Google Scholar
Wells, P. R. A. 1979. P–T conditions in the Moines of the Central Highlands, Scotland. J GEOL SOC LONDON 136, 663–71.CrossRefGoogle Scholar
Winchester, J. A. 1973. Pattern of regional metamorphism suggests a sinistrai displacement of 160 km along the Great Glen fault. NAT PHY SCI 246, 81–4.CrossRefGoogle Scholar
Winchester, J. A. 1974. The zonal pattern of regional metamorphism in the Scottish Caledonides. J GEOL SOC LONDON 130, 509–24.CrossRefGoogle Scholar
Wintsch, R. P. 1975. Feldspathization as a result of deformation. BULL GEOL SOC AM 86, 35–8.2.0.CO;2>CrossRefGoogle Scholar
Wintsch, R. P. 1981. Syntectonic oxidation. AM J SCI 281, 1223–39.CrossRefGoogle Scholar
Wright, A. E. 1980. Problems of Precambrian correlation in mobile belts. In Precambrian in younger folds belts, 7–25. ANNU INST GEOL GEOPHYS BUCHAREST.Google Scholar
Young, G. M., Church, W. R., Choubert, G. A. & Faure-Muret, A. 1977. Stratigraphie correlation of Precambrian rocks (>1.0 b.y. old) of the North Atlantic continents. In Sidorenko, A. (ed.) Correlation of the Precambrian 1, Moscow: Nauka.Google Scholar