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Late Ordovician brachiopod biofacies of the Girvan district, SW Scotland

Published online by Cambridge University Press:  03 November 2011

David A. T. Harper
David A. T. Harper
Affiliation:
David A. T. Harper, Geological Museum, University of Copenhagen, Øster Voldgade 5-7, DK-1350 Copenhagen K,Denmark; e-mail: [email protected]
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Abstract

ABSTRACT

Diverse and abundant brachiopod faunas, associated with unstable outer shelf and slope environments, occur through the Upper Ardmillan Group (upper Caradoc–upper Ashgill) in the Girvan district of SW Scotland. Representatives of the deep-water Foliomena fauna occur intermittently throughout the group, appearing in both the Whitehouse and Drummuck subgroups. This distinctive assemblage of small, thin-shelled brachiopods, including Dedzetina, Christiania, Cyclospira and Foliomena itself, first appeared in South China during the early Caradoc but had colonised the Laurentian margins by the late Caradoc. Within the upper Caradoc–lower Ashgill Whitehouse Subgroup, the Foliomena fauna is interbedded with a variety of other less cosmopolitan deep-water assemblages including the Onniella–Skenidioides and Lingulella–Trimurellina associations. Shallower-water environments in the middle Ashgill Lower Drummuck Subgroup hosted the Fardenia–Eopholidostrophia association in sands, and the Christiania-Leptaena association in muds and silts. The remarkable Lady Burn Starfish Beds in the upper part of the group contain a variety of brachiopod-dominated assemblages including the Eochonetes and Plaesiomys-Schizophorella associations, transported from various shelf locations, within a very diverse mid-Ashgill biota. Nevertheless, elements of the Foliomena fauna persisted to near the top of the Drummuck Subgroup, occurring as rare assemblages in more muddy and silty facies. The upper Ashgill High Mains Formation contains abundant elements of the terminal Ordovician Hirnantia fauna including Eostropheodonta, Hindella and Hirnantia itself, but also some taxa more typical of the Laurentian Edgewood Province. As a whole, the changing brachiopod biofacies monitor environmental fluctuations, on part of the Laurentian margin, driven by mainly eustatic and tectonic events.

Keywords

AshgillBrachiopodaCaradocpalaeobiogeographypalaeoecologypalaeoenvironments
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 91 , Issue 3-4: The Southern Uplands Terrane: Tectonics and Biostratigraphy within the Caledonian Orogen , 2000 , pp. 471 - 477
Copyright
Copyright © Royal Society of Edinburgh 2000

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References

Bluck, B. J. 1983. The 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
Brenchley, P. J. & Cocks, L. R. M. 1982. Ecological associations in a regressive sequence: The latest Ordovician of the Oslo-Asker district, Norway. Palaeontology 25, 783–815.Google Scholar
Brett, C. E., Boucot, A. J. & Jones, B. 1993. Absolute depths of Silurian benthic assemblages. Lethaia 26, 25–40.CrossRefGoogle Scholar
Clarkson, E. N. K., Harper, D. A. T., Owen, A. W. & Taylor, C. 1992. Ordovician faunas in mass-flow deposits in southern Scotland. Terra Nova 4, 245–53.CrossRefGoogle Scholar
Cocks, L. R. M. & Toghill, P. 1973. The biostratigraphy of the Silurian rocks of the Girvan District, Scotland. Quarterly Journal of the Geological Society, London 129, 209–43.CrossRefGoogle Scholar
Donovan, S. K. & Harper, D. A. T. 1993. Pelmatozoan columnals from the High Mains Formation (Hirnantian) of the Girvan district, S.W. Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences 83, 669–77.CrossRefGoogle Scholar
Floyd, J. D., Williams, M. & Rushton, A. W. A. 1999. Late Ordovician (Ashgill) ostracodes from the Drummuck Group, Craighead Inlier, Girvan district, SW Scotland. Scottish Journal of Geology 35, 15–24.CrossRefGoogle Scholar
Fortey, R. A., Harper, D. A. T., Ingham, J. K., Owen, A. W., Parkes, M. A., Rushton, A. W. A. & Woodcock, N. H. 2000. A revised correlation of Ordovician rocks in the British Isles. Geological Society, London, Special Report 24.Google Scholar
Harper, D. A. T. 1979a. The environmental significance of some faunal changes in the Upper Ardmillan succession (upper Ordovician), Girvan, Scotland. In Harris, A. L., Holland, C. H. & Leake, B. E. (eds,) The Caledonides of the British Isles—reviewed, Geological Society, London, Special Publication 8, 439–45. London: Geological Society.Google Scholar
Harper, D. A. T. 1979b. The brachiopod faunas of the Upper Ardmillan succession (upper Ordovician), Girvan (Unpublished Ph.D. Thesis, The Queen's University of Belfast).Google Scholar
Harper, D. A. T. 1981. The stratigraphy and faunas of the Upper Ordovician High Mains Formation of the Girvan district. Scottish Journal of Geology 17, 247–55.CrossRefGoogle Scholar
Harper, D. A. T. 1982. The stratigraphy of the Drummuck Group (Ashgill), Girvan. Geological Journal 17, 251–7.CrossRefGoogle Scholar
Harper, D. A. T. 1984. Brachiopods from the Upper Ardmillan succession (Ordovician) of the Girvan district, Scotland. Palaeontographical Society Monograph Part 1, 136, 1–78.CrossRefGoogle Scholar
Harper, D. A. T. 1988. Ordovician-Silurian junctions in the Girvan district, S.W. Scotland. Bulletin of the British Museum of Natural History (Geology) 43, 45–52.Google Scholar
Harper, D. A. T. 1989. Brachiopods from the Upper Ardmillan succession (Ordovician) of the Girvan district, Scotland. Palaeontographical Society Monograph Part 2, 142, 78–128.Google Scholar
Harper, D. A. T., Jia-yu, Rong & Ren-bin, Zhan 1999. Late Ordovician development of deep-water brachiopod faunas. Acta Universitatis Carolinae, Geologica 1999, 1/2, 351–3.Google Scholar
Harper, D. A. T. & Owen, A. W. (eds) 1996. Fossils of the Upper Ordovician. Palaeontological Association Field Guides to Fossils 7. London: Palaeontological Association.Google Scholar
Ince, D. M. 1984. Sedimentation and tectonism in the middle Ordovician of the Girvan district, SW Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences 75, 225–37.CrossRefGoogle Scholar
Ingham, J. K. 1978. The geology of a continental margin 2: middle and late Ordovician transgression, Girvan. In Bowes, D. R. & Leake, B. E. (eds,) Crustal evolution in northwestern Britain and adjacent regions. Geological Journal Special Issue 10, 163–76. Chichester: John Wiley.Google Scholar
Ingham, J. K. 1993. Excursion 30 Girvan Foreshore. In Lawson, J. D. & Weedon, D. S. (eds) Geological excursions around Glasgow and Girvan, 396–416. Glasgow: Glasgow Geological Society.Google Scholar
Lamont, A. 1935. The Drummuck Group, Girvan: stratigraphical revision with descriptions of new fossils from the lower part of the group. Transactions of the Geological Society of Glasgow 19, 288–334.CrossRefGoogle Scholar
Lapworth, C. 1882. The Girvan Succession. Part 1. Stratigraphy. Quarterly Journal of the Geological Society, London 38, 537–666.CrossRefGoogle Scholar
Lockley, M. G. 1983. A review of brachiopod dominated palaeocommunities from the type Ordovician. Palaeontology 26, 111–45.Google Scholar
Mitchell, W. I. 1977. The Ordovician Brachiopoda from Pomeroy, Co. Tyrone. Palaeontographical Society Monograph 130, 1–138.Google Scholar
Neuman, R. B. 1968. Palaeogeographic implications of Ordovician shelly fossils in the Magog belt of the Northern Appalachian region. In Zen, E. A., White, W. S., Hadley, J. B. & Thompson, J. B. jnr (eds) Studies of Appalachian geology: Northern and Maritime, 35–48. New York: Interscience.Google Scholar
Neuman, R. B., Bruton, D. L. & Pojeta, J. 1997. Fossils from the Ordovician Upper Hovin Group (Caradoc-Ashgill), Trondheim region, Norway. Bulletin Norges Geologiske Undersøkelse 432, 25–58.Google Scholar
Pollock, S. J., Harper, D. A. T. & Rohr, D. 1994. A near-shore Ordovician gastropod and brachiopod fauna from northernmost Maine. Journal of Paleontology 68, 925–37.CrossRefGoogle Scholar
Jia-yu, Rong, Ren-bin, Zhan & Harper, D. A. T. 1999. Late Ordovician (Caradoc–Ashgill) brachiopod faunas with Foliomena based on data from China. Palaios 14, 412–31.CrossRefGoogle Scholar
Jia-yu, Rong & Harper, D. A. T. 1988. A global synthesis of the latest Ordovician Hirnantian brachiopod faunas. Transactions of the Royal Society of Edinburgh: Earth Sciences 79, 383–402.CrossRefGoogle Scholar
Jia-yu, Rong & Harper, D. A. T. 2000 (for 1999). Brachiopod survival and recovery from the latest Ordovician mass extinctions in South China. Geological Journal 34, 321–48.3.0.CO;2-I>CrossRefGoogle Scholar
Ross, C. A. & Ross, J. R. P. 1995. North American Ordovician depositional sequences and correlations. In Cooper, J. D., Droser, M. D. & Finney, S. C. (eds) Ordovician Odyssey: Short papers for the Seventh International Symposium on the Ordovician System, 309–13. Fullerton, CA: Pacific Section for the Sedimentary Geology (SEPM).Google Scholar
Ryan, P. D., Ryan, M. & Harper, D. A. T. 1999. Sedation: a new approach. In Harper, D. A. T. (ed.) Numerical palaeobiology, 433–19. Chichester: John Wiley.Google Scholar
Williams, A. 1962. The Barr and Lower Ardmillan Series (Caradoc) of the Girvan district, south-west Ayrshire. Geological Society, London, Memoir 3, 1–267.Google Scholar