Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-22T13:02:28.113Z Has data issue: false hasContentIssue false
  • English
  • Français

Lithostratigraphy of the Ordovician rocks in the Southern Uplands: Crawford Group, Moffat Shale Group, Leadhills Supergroup

Published online by Cambridge University Press:  03 November 2011

J. D. Floyd
J. D. Floyd
Affiliation:
British Geological Survey, Murchison House, West Mains Road, Edinburgh, EH9 3LA, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

A formal lithostratigraphy is erected for all the Ordovician rocks in the Southern Uplands of Scotland. At the base of the succession, the Crawford Group (Arenig–Llanvirn) encompasses the chert and lava sequences usually associated with the tract-bounding faults, and includes the only proven Arenig rocks in the Southern Uplands. The overlying Moffat Shale Group (Caradoc–Llandovery) is now restricted to the black and grey graptolitic shales which succeed the grey and red chert successions. The Leadhills Supergroup (Caradoc–Ashgill) forms the overwhelming bulk of the sedimentary succession and includes the thick Ordovician turbidite successions of the Northern Belt. Existing stratigraphical terminology is reviewed, revised or extended as appropriate to maintain maximum continuity with current usage. Type sections for each unit are either proposed, where newly defined or revised, or cited in the case of existing definitions.

Keywords

ArenigAshgillCaradocCentral BeltgreywackeLlanvirnNorthern Beltturbidite.
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 86 , Issue 3 , 1995 , pp. 153 - 165
Copyright
Copyright © Royal Society of Edinburgh 1995

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

Anderson, T. B. & Oliver, G. J. H. 1986. The Orlock Bridge Fault: a major Late Caledonian sinistral fault in the Southern Uplands terrane, British Isles. TRANS R SOC EDINBURGH: EARTH SCI 77, 203–22.CrossRefGoogle Scholar
Anderson, T. B. & Oliver, G. J. H. 1987. Reply to “Constraints on the significance of the Orlock Bridge Faultwithin the Scottish Southern Uplands”, a discussion of “The Orlock Bridge Fault: a major Late Caledonian sinistral fault in the Southern Uplands terrane, British Isles”. TRANS R SOC EDINBURGH: EARTH SCI 78, 223–5.CrossRefGoogle Scholar
Armstrong, H. A., Clarkson, E. N. K. & Owen, A. W. 1990. A new Lower Ordovician conodont faunule from the Northern Belt of the Southern Uplands. SCOTT J GEOL 26, 47–52.CrossRefGoogle Scholar
Armstrong, H. A., Owen, A. W., Scrutton, C. T., Clarkson, E. N. K. & Taylor, C. M. (in press) Palaeontological constraints on the evolution of the Northern Belt, SouthernUplands–implications for the Southern Uplands controversy. J GEOL SOC LONDON.Google Scholar
Barrett, T. J., Jenkyns, H. C, Leggett, J. K. & Robertson, A. H. F. 1982. Comment on ‘Age and origin of Ballantrae ophiolite and its significance to the Caledonian orogeny and the Ordovician time scale’. GEOLOGY 10, 331.2.0.CO;2>CrossRefGoogle Scholar
Batchelor, R. A. & Weir, J. A. 1988. Metabentonite geochemistry: magmatic cycles and graptolite extinctions at Dob's Linn, southern Scotland. TRANS R SOC EDINBURGH: EARTH SCI 79, 19–41.CrossRefGoogle Scholar
British Geological Survey 1992. The Rhins of Galloway. Scotland, Sheets 1 and 3 withparts of 7 and 4W. SolidGeology. 1:50 000. Keyworth, Nottingham: British Geological Survey.Google Scholar
British Geological Survey 1993. Regional geochemistry of southern Scotland and part of northern England. Keyworth, Nottingham: British Geological Survey.Google Scholar
British Geological Survey 1994a. Carrick. Scotland Sheet 8W. Solid Geology. 1:50000. Keyworth, Nottingham: British Geological Survey.Google Scholar
British Geological Survey 1994b. Loch Doon. Scotland Sheet 8E. Solid Geology. 1:50 000. Keyworth, Nottingham, British Geological Survey.Google Scholar
Cameron, I. B., Stone, P. & Smellie, J. 1986. Geology of the country around Girvan. Explanation of 1:50 000 Scotland Sheet 7. London: HMSO for British Geological Survey.Google Scholar
Casey, D. M. 1983. Geological studies in the Central Belt of the Eastern Southern Uplands of Scotland. University of Oxford PhD thesis (unpubl.).Google Scholar
Clarkson, E. N. K., Harper, D. A. T., Owen, A. W. & Taylor, C. M. 1992. Ordovician faunas in mass-flow deposits, Southern Scotland. TERRA NOVA 4, 245–53.CrossRefGoogle Scholar
Craig, G. Y. & Walton, E. K. 1959. Sequence and structure in the Silurian rocks in Kirkcudbrightshire. GEOL MAG 96, 209–20.CrossRefGoogle Scholar
Duller, P. R. & Floyd, J. D. 1995. Turbidite geochemistry and provenance studies in the Southern Uplands of Scotland. GEOL MAG 132, 557–69.CrossRefGoogle Scholar
Elders, C. F. 1987. The provenance of granite boulders in conglomerates of the Northern and Central Belts of the Southern Uplands of Scotland. J GEOL SOC LONDON 144, 853–63.CrossRefGoogle Scholar
Evans, J. A., Stone, P. & Floyd, J. D. 1991. Isotopic characteristics of Ordovician greywacke provenance in the Southern Uplands of Scotland. In Morton, A. C, Todd, S. P. & Haughton, P. D. W. (eds) Developments in sedimentary provenance studies, 161–72. GEOL SOC LONDON SPEC PUBL 57.CrossRefGoogle Scholar
Finney, S. C. & Bergstrom, S. M. 1986. Biostratigraphy of the Ordovician Nemagraptus gracilis Zone. In Hughes, C. P. & Rickards, R. B. (eds) Palaeoecology andbiostratigraphy of graptolites, 47–59. GEOL SOC LONDON SPEC PUBL 20.CrossRefGoogle Scholar
Floyd, J. D. 1976. The Ordovician rocks of West Nithsdale. University of St Andrews, PhD thesis (unpubl.).Google Scholar
Floyd, J. D. 1982. Stratigraphy of a flysch succession: the Ordovician of W Nithsdale, SW Scotland. TRANS R SOC EDINBURGH: EARTH SCI 73, 1–9.CrossRefGoogle Scholar
Floyd, J. D. 1994. The derivation and definition of the ‘Southern Upland Fault’: a review of the Midland Valley-Southern Uplands terrane boundary. SCOTT J GEOL 30, 51–62.CrossRefGoogle Scholar
Floyd, J. D. (in press). Geology of the Carrick-Loch Doon district. Sheets 8W and 8E (Scotland). MEM BR GEOL SURV.Google Scholar
Floyd, J. D. & Kimbell, G. S. 1995. Magnetic and tectonostratigraphic correlation at a terrane boundary: the Tappins Group of the Southern Uplands. GEOL MAG 132, 515–21.CrossRefGoogle Scholar
Floyd, J. D. & Rushton, A. W. A. 1993. Ashgill greywackes in the Southern Uplands of Scotland: an extension of the Ordovician succession in the Northern Belt. TRANS R SOC EDINBURGH: EARTH SCI 84, 79–85.CrossRefGoogle Scholar
Floyd, J. D. & Stone, P. 1992. Tweedsmuir. In McAdam, A. D., Clarkson, E. N. K. & Stone, P. (eds) Scottish Borders geology. An excursion guide, 147–58. Edinburgh: Scottish Academic Press.Google Scholar
Floyd, J. D. & Trench, A. 1989. Magnetic susceptibility contrasts in Ordovician greywackes of the Southern Uplands of Scotland. J GEOL SOC LONDON 146, 77–83.CrossRefGoogle Scholar
Floyd, J. D., Stone, P., Barnes, R. P. & Lintern, B. C. 1987.Constraints on the significance of the Orlock Bridge Fault within the Scottish Southern Uplands, a discussion of “The Orlock Bridge Fault: a major Late Caledonian sinistral fault in the Southern Uplands terrane, British Isles”. TRANS R SOC EDINBURGH: EARTH SCI 78, 219–21.CrossRefGoogle Scholar
Geikie, A. 1871. Explanation of Sheet 15. Parts of Dumfriesshire, Lanarkshire and Ayrshire. MEM GEOL SURV SCOTLAND.Google Scholar
Hepworth, B. C. 1981. Geology of the rocks between Leadhills and Abington, Lanarkshire. University of St Andrews PhD thesis (unpubl.).Google Scholar
Hepworth, B. C, Oliver, G. J. H. & McMurtry, M. J., 1982. Sedimentology, volcanism, structure and metamorphism of the northern margin of a Lower Palaeozoic accretionary complex: Bail Hill-Abington area of the Southern Uplands of Scotland. In Leggett, J. K. (ed) Trench-forearc geology: Sedimentation and tectonics on modern andancient active plate margins, 521–34. GEOL SOC LONDON SPEC PUBL 10.CrossRefGoogle Scholar
Holroyd, J. 1978. The sedimentological and geotectonic significance of Lower Palaeozoic flysch rudites. University of Wales PhD thesis (unpubl.).Google Scholar
Hughes, R. A. & Boland, M. 1995. The Ordovician and Silurian rocks of ScottishSheet 24E (Peebles). BR GEOL SURV TECH REP WA/95/14.Google Scholar
Ince, D. 1984. Sedimentation and tectonism in the Middle Ordovician of the Girvan district, SW Scotland. TRANS R SOC EDINBURGH: EARTH. SCI 75, 225–37.CrossRefGoogle Scholar
Kassi, A. M. 1984. Lower Palaeozoic geology of the Gala area, Borders Region, Scotland. University of St Andrews PhD thesis (unpubl.).Google Scholar
Kassi, A. M. & Weir, J. A. 1993. Depositional and geotectonic history of the Gala area, eastern Southern Uplands, Scotland. TRANS R SOC EDINBURGH: EARTH SCI 84, 161–73.CrossRefGoogle Scholar
Kelling, G. 1958. The Ordovician rocks of the Rhinns of Galloway. University ofEdinburgh, PhD thesis (unpubl.).CrossRefGoogle Scholar
Kelling, G. 1961. The stratigraphy and structure of the Ordovician rocks of the Rhinnsof Galloway. Q J GEOL SOC LONDON 117, 37–75.CrossRefGoogle Scholar
Kelling, G. 1962. The petrology and sedimentation of Upper Ordovician rocks in the Rhins of Galloway, south-west Scotland. TRANS R SOC EDINBURGH: EARTH SCI 65, 107–37.CrossRefGoogle Scholar
Kelling, G. & Welsh, W. 1970. The Loch Ryan fault. SCOTT J GEOL 6, 266–71.CrossRefGoogle Scholar
Lamont, A. 1975. Noble House, Lamancha. In Craig, G. Y. & Duff, P.McL, D. (eds) The geology of the Lothians and south east Scotland. An excursion guide, 158–66. Edinburgh: Scottish Academic Press.Google Scholar
Lamont, A. & Lindstrom, M. 1957. Arenigian and Llandeilian cherts identified in the Southern Uplands by means of conodonts, etc. TRANS EDINBURGH GEOL SOC 17, 60–70.CrossRefGoogle Scholar
Lapworth, C. 1878. The Moffat Series. Q J GEOL SOC LONDON 34, 240–346.CrossRefGoogle Scholar
Leggett, J. K. 1978. Studies in the Ordovician rocks of the Southern Uplands, with particular reference to the Northern Belt. University of Oxford, DPhil thesis (unpubl.).Google Scholar
Leggett, J. K. 1980a. The sedimentological evolution of a Lower Palaeozoic accretionary fore-arc in the Southern Uplands of Scotland. SEDIMENTOLOGY 27, 401–17.CrossRefGoogle Scholar
Leggett, J. K. 1980b. Palaeogeographic setting of the Wrae Limestone: an Ordovician submarine-slide deposit in Tweeddale. SCOTT J GEOL 16, 91–104.CrossRefGoogle Scholar
Leggett, J. K., McKerrow, W. S. & Eales, M. H. 1979. The Southern Uplands of Scotland: a Lower Palaeozoic accretionary prism. J GEOL SOC LONDON 136, 755–70.CrossRefGoogle Scholar
McKerrow, W. S., Leggett, J. K. & Eales, M. H. 1977. Imbricate thrust model of the Southern Uplands of Scotland. NATURE, LONDON 267, 237–9.CrossRefGoogle Scholar
McMurtry, M. J. 1980. The Ordovician rocks of the Bail Hill area, Sanquhar, South Scotland: Volcanism and sedimentation in the Iapetus Ocean. University of St Andrews, PhD thesis (unpubl.).Google Scholar
Merriman, R. J. & Roberts, B. 1990. Metabentonites in the Moffat Shale Group, Southern Uplands of Scotland: geochemical evidence of ensialic, marginal basin volcanism. GEOL MAG 127, 259–71.CrossRefGoogle Scholar
Owen, A. W. & Clarkson, E. N. K. 1992. Trilobites from Kilbucho and Wallace's Cast and the location of the Northern Belt of the Southern Uplands during the late Ordovician. SCOT J GEOL 28, 3–17.CrossRefGoogle Scholar
Peach, B. N. & Horne, J. 1899. The Silurian Rocks of Britain, Volume 1. Scotland. MEM GEOL SURV UK.Google Scholar
Phillips, E. R., Barnes, R. P., Merriman, R. J. & Floyd, J. D. 1995. The tectonic significance of Ordovician basic igneous rocks in the Southern Uplands, SW Scotland. GEOL MAG 132, 549–56.CrossRefGoogle Scholar
Rushton, A. W. A. & Stone, P. 1991. Terrigenous input to the Moffat Shale sequence, Southern Uplands. SCOT J GEOL 27, 167–9.CrossRefGoogle Scholar
Rushton, A. W. A. & Tunnicliff, S. P. 1996. Graptolites: Ordovician and Silurian biostratigraphy. In Stone, P. (ed.) Geology in southwest Scotland: an excursion guide. Keyworth: British Geological Survey.Google Scholar
Stone, P. 1995. Geology of the Rhins of Galloway district. Sheets 1 & 3, Scotland. MEM BR GEOL SURV.Google Scholar
Stone, P., Floyd, J. D., Barnes, R. P. & Lintern, B. C. 1987. A sequential back-arc and foreland basin thrustduplex model for the Southern Uplands of Scotland. J GEOL SOC LONDON 144, 753–64.CrossRefGoogle Scholar
Styles, M. T., Perez-Alvarez, M. & Floyd, J. D. 1995. Pyroxenous greywackes in the Southern Uplands and theirpetrotectonic implications. GEOL MAG 132, 539–47.CrossRefGoogle Scholar
Styles, M. T., Stone, P. & Floyd, J. D. 1989. Arc detritus in the Southern Uplands: mineralogical characterisation of a ‘missing’ terrane. J GEOL SOC LONDON 146, 397–400.CrossRefGoogle Scholar
Thirlwall, M. F. 1981. Peralkaline rhyolites from the Ordovician Tweeddale Lavas, Peeblesshire, Scotland. GEOL J 16, 41–4.CrossRefGoogle Scholar
Thirlwall, M. F. & Bluck, B. J. 1984. Sr-Nd isotope and geological evidence that the Ballantrae “ophiolite”, SW Scotland, is polygenetic. In Gass, I. G., Lippard, S. J. & Shelton, A. W. (eds) Ophiolites and oceanic lithosphere, 215–30. GEOL SOC LONDON SPEC PUBL 13.CrossRefGoogle Scholar
Toghill, P. 1970. Highest Ordovician (Hartfell Shales) graptolitic faunas from the Moffat area, south-west Scotland. BULL BR MUS NAT HIST GEOL 19, 1–26.Google Scholar
Walton, E. K. 1955. Silurian greywackes in Peeblesshire. PROC R SOC EDINBURGH B65, 327–57.Google Scholar
Walton, E. K. 1956. Two Ordovician conglomerates in south Ayrshire. TRANS GEOL SOC GLASGOW 22, 133–56.CrossRefGoogle Scholar
Walton, E. K. & Oliver, G. J. H. 1991. Lower Palaeozoic-Stratigraphy.In Craig, G. Y. (ed.) Geology of Scotland (3rd edn). London: The Geological Society.Google Scholar
Webb, B., Rushton, A. W. A. & White, D. E. 1993. Mqffatdale and the upper Ettrick Valley: a description of the solid geology of parts of 1:25000 sheets NT 10, 11, 20 and 21. Classical areas of British Geology. London: HMSO for British Geological Survey.Google Scholar
Welsh, W. 1964. The Ordovician rocks of north-west Wigtownshire. University of Edinburgh, PhD thesis (unpubl.).Google Scholar
Williams, S. H. 1980. An Excursion Guide to Dob's Linn. PROC GEOL SOC GLASGOW, 121/122, 13-18.Google Scholar
Williams, S. H. 1982a. Upper Ordovician graptolites from the top Lower Hartfell Shale Formation (D. clingani and P. Hnearis Zones) near Moffat, southern Scotland. TRANS R SOC EDINBURGH: EARTH SCI 72, 229–55.CrossRefGoogle Scholar
Williams, S. H. 1982b. The Late Ordovician graptolitic fauna of the Anceps Bands at Dob's Linn, southern Scotland. GEOLOGICA ET PALAEONTOLOGICA 16, 29–56.Google Scholar
Williams, S. H. 1983. The Ordovician-Silurian boundary graptolite fauna of Dob's Linn, Southern Scotland. PALAEONTOLOGY 26, 605–39.Google Scholar
Williams, S. H. 1986. Top Ordovician and lowest Silurian of Dob's Linn. In Hughes, C. P. & Rickards, R. B. (eds) Palaeoecology and hiostratigraphy of graptolites. GEOL SOC LONDON SPEC PUBL 20, 165–71.CrossRefGoogle Scholar
Williams, S. H. 1987. Upper Ordovician graptolites from the D. complanatus Zone of theMoffat and Girvan districts and their significance for correlation. SCOTT J GEOL 23, 65–92.CrossRefGoogle Scholar
Williams, S. H. 1994. Revision and definition of the C. wilsoni Zone (middle Ordovician) of southern Scotland. TRANS R SOC EDINBURGH: EARTH SCI 85, 143–157.CrossRefGoogle Scholar
Zalasiewicz, J. A., Rushton, A. W. A. & Owen, A. W. 1995. Late Caradoc graptolite faunal gradients across th Iapetus Ocean. GEOL MAG 132, 611–18.CrossRefGoogle Scholar