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New evidence that the Lower Cambrian Leny Limestone at Callander, Perthshire, belongs to the Dalradian Supergroup, and a reassessment of the ‘exotic’ status of the Highland Border Complex

Published online by Cambridge University Press:  01 May 2009

P. W. G. Tanner
Affiliation:
Department of Geology and Applied Geology, University of Glasgow, Glasgow G12 8QQ, UK

Abstract

The Lower Cambrian Leny Limestone at Callander in Scotland lies within a sequence of palecoloured grits and dark slates (here named the Keltie Water Grit Formation (KWGF)) which has lithological similarities with members of the Highland Border Complex (HBC) (Ordovician) seen elsewhere along the Highland Border. The Keltie Water Grit Formation has a transitional boundary with a grit-slate sequence of undoubted Dalradian parentage; as the ‘Leny Grits’ of previous workers include both the KWGF and part of the Dalradian sequence, this term is now rendered invalid. The entire sequence youngs upwards from the Dalradian to the top of the overlying Keltie Water Grit Formation, shares the same structural sequence and geometry, and has the same facing and vergence direction on the main cleavage. All field and petrographic data are consistent with a minimum age of post-early Cambrian for the Grampian event, the main orogenic event to affect the Dalradian. Examination of critical sections elsewhere across the Highland Border shows that there is an apparently consistent stratigraphical and structural relationship between the Highland Border Complex and the Dalradian which, as suggested by some previous workers, would require the Grampian event to be post-Arenig in age. However, we are faced with a so-far unresolved paradox that there are certain palaeontological and radiometric data which are in conflict with this conclusion, and support the alternative hypothesis that the Highland Border Complex docked with the Dalradian in post-Ordovician times.

Type
Articles
Copyright
Copyright © Cambridge University Press 1995

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References

Anderson, J. G. C., 1947. The geology of the Highland Border: Stonehaven to Arran. Transactions of the Royal Society of Edinburgh 61, 479515.CrossRefGoogle Scholar
Anderson, J. G. C., & Pringle, J., 1944. The Arenig rocks of Arran, and their relationship to the Dalradian Series. Geological Magazine 81, 81–7.CrossRefGoogle Scholar
Barrow, G., 1901. On the occurrence of Silurian(?) rocks in Forfarshire and Kincardineshire along the Eastern Border of the Highlands. Quarterly Journal of the Geological Society, London 57, 328–45.CrossRefGoogle Scholar
Barrow, G., 1912. On the geology of Lower Deeside and the Southern Highland Border. Proceedings of the Geologists’ Association 23, 274–90.CrossRefGoogle Scholar
Bluck, B. J., 1983. Role of the Midland Valley of Scotland in the Caledonian orogeny. Transactions of the Royal Society of Edinburgh: Earth Sciences 74, 119–36.CrossRefGoogle Scholar
Bluck, B. J., 1985. The Scottish paratectonic Caledonides. Scottish Journal of Geology 21, 437–64.CrossRefGoogle Scholar
Bluck, B. J., 1990. Terrane provenance and amalgamation: examples from the Caledonides. Philosophical Transactions of the Royal Society, London 331, 599609.Google Scholar
Bowes, D. R., 1992. Loch Lomondside. In Geological excursions around Glasgow and Girvan (eds Lawson, J. D. and Weedon, D. S.), pp. 141–53. Geological Society of Glasgow.Google Scholar
Bowring, S. A., Grotzinger, J. P., Isachsen, C. E., Knoll, A. H., Peletchaty, S. M., & Kolosov, P., 1993. Calibrating rates of Cambrian evolution. Science 261, 1293–8.CrossRefGoogle ScholarPubMed
Brasier, M. D., Ingham, J. K., & Rushton, A. W. A., 1992. Cambrian. In Atlas of Palaeogeography and Lithofacies (eds Cope, J. C. W., Ingham, J. K. and Rawson, P. F.), pp. 1318. Geological Society of London, Memoir no. 13.Google Scholar
Brown, P. E., Miller, J. A., Soper, N. J., & York, D., 1965. Potassium-argon age pattern of the British Caledonides. Proceedings of the Yorkshire Geological Society 35, 103–38.CrossRefGoogle Scholar
Burton, C. J., Hocken, C., MacCallum, D., & Young, M. E., 1983. Chitinozoa and the age of the Margie Limestone of the North Esk. Proceedings of the Geological Society of Glasgow 1982–83, 2732.Google Scholar
Curry, G. B., Ingham, J. K., Bluck, B. J., & Williams, A., 1982. The significance of a reliable Ordovician age for some Highland Border rocks in Central Scotland. Journal of the Geological Society London 139, 451–4.CrossRefGoogle Scholar
Curry, G. B., Bluck, B. J., Burton, C. J., Ingham, J. K., Siveter, D. J., & Williams, A., 1984. Age, evolution and tectonic history of the Highland Border Complex, Scotland. Transactions of the Royal Solciety of Edinburgh: Earth Sciences 75, 113–33.CrossRefGoogle Scholar
Dempster, T. J., 1985. Uplift patterns and orogenic evolution in the Scottish Dalradian. Journal of the Geological Society, London 142, 111–28.CrossRefGoogle Scholar
Geikie, A., 1897. Annual Report of the Geological Survey for 1896, p. 28.Google Scholar
Halliday, A. N., Graham, C. M., Aftalion, M., & Dymoke, P., 1989. The depositional age of the Dalradian Supergroup: U-Pb and Sm-Nd isotopic studies of the Tayvallich Volcanics, Scotland. Journal of the Geological Society, London 146, 36.CrossRefGoogle Scholar
Harper, C. T., 1967. The geological interpretation of potassium-argon ages of metamorphic rocks from the Scottish Caledonides. Scottish Journal of Geology 3, 4666.CrossRefGoogle Scholar
Harris, A. L., 1962. Dalradian geology of the Highland Border near Callander. Bulletin of the Geological Survey of Great Britain 19, 115.Google Scholar
Harris, A. L., 1969. The relationships of the Leny Limestone to the Dalradian. Scottish Journal of Geology 5, 187–90.Google Scholar
Harris, A. L., & Fettes, D. J., 1972. Stratigraphy and structure of Upper Dalradian rocks at the Highland Border. Scottish Journal of Geology 8, 253–64.Google Scholar
Harris, A. L., Bradbury, H. J., & McGonigal, M. H., 1976. The evolution and transport of the Tay Nappe. Scottish Journal of Geology 12, 103–13.CrossRefGoogle Scholar
Harte, B., Booth, J. E., Dempster, T. J., Fettes, D. J., Mendum, J. R., & Watts, D., 1984. Aspects of the postdepositional evolution of Dalradian and Highland Border Complex rocks in the Southern Highlands of Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences 75, 151–63.CrossRefGoogle Scholar
Henderson, W. G., & Fortey, N. J., 1982. Highland Border rocks at Loch Lomond and Aberfoyle. Scottish Journal of Geology 18, 227–45.Google Scholar
Henderson, W. G., & Robertson, A. H. F., 1982. The Highland Border rocks and their relationship to marginal basin development in the Scottish Caledonides. Journal of the Geological Society, London 139, 433–50.CrossRefGoogle Scholar
Ingham, K. I., Curry, G. B., & Williams, A., 1985. Early Ordovician Dounans Limestone fauna, Highland Border Complex, Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences 76, 481513.Google Scholar
Isachsen, C. E., Bowring, S. A., Landing, E., & Samson, D., 1994. New constraint on the division of Cambrian time. Geology 22, 496–8.2.3.CO;2>CrossRefGoogle Scholar
Jehu, T. J., & Campbell, R., 1917. The Highland Border rocks of the Aberfoyle district. Transactions of the Royal Society of Edinburgh 52, 175212.Google Scholar
Johnson, M. R. W., & Harris, A. L., 1965. Is the Tay Nappe post-Arenig? Scottish Journal of Geology 1, 217–19.CrossRefGoogle Scholar
Johnson, M. R. W., & Harris, A. L., 1967. Dalradian-?Arenig relations in parts of the Highland Border, Scotland, and their significance in the chronology of the Caledonian orogeny. Scottish Journal of Geology 3, 116.CrossRefGoogle Scholar
McKerrow, W. S., & Atkins, F. B., 1989. Isle of Arran, 2nd edn. The Geologists’ Association.Google Scholar
Pankhurst, R. J., & Pidgeon, R. T., 1976. Inherited isotope systems and the source region pre-history of early Caledonian granites in the Dalradian series of Scotland. Earth and Planetary Science Letters 31, 5568.CrossRefGoogle Scholar
Pidgeon, R. T., & Compston, W., 1992. A SHRIMP ion microprobe study of inherited and magmatic zircons from four Scottish Caledonian granites. Transactions of the Royal Society of Edinburgh: Earth Sciences 83, 473–83.CrossRefGoogle Scholar
Pringle, J., 1939. The discovery of Cambrian trilobites in the Highland Border rocks near Callander, Perthshire. Report of the British Associationfor the Advancement of Science 1, 252.Google Scholar
Pringle, J., 1941. On the relationship of the Green Conglomerate to the Margie Grits in the North Esk, near Edzell; and on the probable age of the Margie Limestone. Transactions of the Geological Society of Glasgow 20, 136–40.Google Scholar
Rogers, G., Dempster, T. J., Bluck, B. J., & Tanner, P. W. G., 1989. A high precision U-Pb age for the Ben Vuirich granite: implications for the evolution of the Scottish Dalradian Supergroup. Journal of the Geological Society, London 146, 789–98.CrossRefGoogle Scholar
Shackleton, R. M., 1958. Downward-facing structures of the Highland Border. Quarterly Journal of the Geological Society, London 113, 361–92.CrossRefGoogle Scholar
Soper, N. J., 1994. Neoproterozoic sedimentation on the northeast margin of Laurentia and the opening of Iapetus. Geological Magazine 131, 291–9.CrossRefGoogle Scholar
Stone, M., 1957. The Aberfoyle Anticline, Callander, Perthshire. Geological Magazine 94, 265–76.CrossRefGoogle Scholar
Tanner, P. W. G., 1992. Rosneath Peninsula and Loch Long. In Geological excursions around Glasgow and Girvan (eds Lawson, J. D. and Weedon, D. S.), pp. 159–85. Geological Society of Glasgow.Google Scholar
Tanner, P. W. G., in press. Significance of a pre-intrusion fabric in the contact metamorphic aureole of the 590 Ma Ben Vuirich Granite, Perthshire, Scotland. Geological Magazine.Google Scholar
Tanner, P. W. G., & Leslie, A. G., 1994. A pre-D2 age for the 590 Ma Ben Vuirich Granite in the Dalradian of Scotland. Journal of the Geological Society, London 151, 209–12.CrossRefGoogle Scholar