At what stratigraphical level is the mid Ludfordian (Ludlow, Silurian) positive carbon isotope excursion in the type Ludlow area, Shropshire, England?


Authors: Loydell DK, Frýda J

Published in: Bulletin of Geosciences, volume 86, issue 2; pages: 197 - 208; Received 17 January 2011; Accepted in revised form 28 March 2011; Online 13 April 2011

Keywords: Silurian, Ludlow, carbon isotopes, conodonts, chitinozoans, thelodonts, stratigraphy,

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The balance of evidence suggests that the mid Ludfordian positive carbon isotope excursion (CIE) commences in the Ludlow area, England in the uppermost Upper Whitcliffe Formation, with the excursion continuing into at least the Platyschisma Shale Member of the overlying Downton Castle Sandstone Formation. The Ludlow Bone Bed Member, at the base of the Downton Castle Sandstone Formation has previously been considered to be of PA™A­dolA­ age. Conodont and thelodont evidence, however, are consistent with the mid Ludfordian age proposed here. New δ13Corg data are presented from Weir Quarry, W of Ludlow, showing a pronounced positive excursion commencing in the uppermost Upper Whitcliffe Formation, in strata with a palynologically very strong marine influence. Elsewhere in the world, the mid Ludfordian positive CIE is associated with major facies changes indicated shallowing; the lithofacies evidence from the Ludlow area is consistent with this. There appears not to be a major stratigraphical break at the base of the Ludlow Bone Bed Member.


Aldridge, R.J. & Schönlaub, H.-P. 1989. Conodonts, 274-279. In Holland, C.H.&Bassett, M.G. (eds) A global standard for the Silurian System. National Museum of Wales, Cardiff.

Andrew, A.S., Hamilton, P.J., Mawson, R., Talent, J.A. & Whitford, D.J. 1994. Isotopic correlation tools in the mid-Palaeozoic and their relation to extinction events. Australian Petroleum Exploration Association Journal 34, 268-277.View article

Barrick, J.E., Kleffner, M.A., Gibson, M.A., Peavey, F.N. & Karlsson, H.R. 2010. The mid-Ludfordian Lau Event and carbon isotope excursion (Ludlow, Silurian) in southern Laurentia - preliminary results. Bollettino della Societa Paleontologica Italiana 49, 13-33.

Bassett, M.G., Lawson, J.D. & White, D.E. 1982. The Downton Series as the fourth series of the Silurian System. Lethaia 15, 1-24.View article

Cherns, L. 1982. Palaeokarst, tidal erosion surfaces and stromatolites in the Silurian Eke Formation of Gotland, Sweden. Sedimentology 29, 819-833.View article

Corfield, R.M., Siveter, D.J., Cartlidge, J.E. & McKerrow, W.S. 1992. Carbon isotope excursion near the Wenlock-Ludlow (Silurian) boundary in the Anglo-Welsh area. Geology 20, 371-374.View article

Corradini, C. 2009. Looking for a late Silurian Standard Conodont Zonation: still a long way to go. Rendiconti della Societa Paleontologica Italiana 3, 273-274.

Corradini, C. & Serpagli, E. 1999. A Silurian conodont biozonation from late Llandovery to end Přídolí in Sardinia (Italy). Bollettino della Societa Paleontologica Italiana 37, 255-273.

Cramer, B.D., Kleffner, M.A. & Saltzman, M.R. 2006. The late Wenlock Mulde positive carbon isotope (?13Ccarb) excursion in North America. GFF 128, 85-90.View article

Cramer, B.D., Loydell, D.K., Samtleben, C., Munnecke, A., Kaljo, D., Männik, P., Martma, T., Jeppsson, L., Kleffner, M.A., Barrick, J. E., Johnson, C.A., Emsbo, P., Joachimski, M.M., Bickert, T. & Saltzman, M.R. 2010. Testing the limits of Paleozoic chronostratigraphic correlation via high-resolution (<500 k.y.) integrated conodont, graptolite, and carbon isotope (?13Ccarb) biochemostratigraphy across the Llandovery-Wenlock (Silurian) boundary: is a unified Phanerozoic time scale achievable? Geological Society of America Bulletin 122, 1700-1716.View article

Eriksson, M.J. & Calner, M. 2008. A sequence stratigraphical model for the late Ludfordian (Silurian) of Gotland, Sweden: implications for timing between changes in sea level, palaeoecology, and the global carbon cycle. Facies 54, 253-276.View article

Grahn, Y. 1996. Upper Silurian (upper Wenlock-lower Pridoli) Chitinozoa and biostratigraphy of Skane, southern Sweden. GFF 118, 237-250.View article

Holland, C.H., Lawson, J.D. & Walmsley, V.G. 1963. The Silurian rocks of the Ludlow district, Shropshire. Bulletin of the British Museum (Natural History) Geology 8, 95-171, pls 1-7.

Jaglin, J.C. & Paris, F. 2002. Biostratigraphy, biodiversity and palaeogeography of late Silurian chitinozoans from A1-61 borehole (north-western Libya). Review of Palaeobotany and Palynology 118, 335-358.View article

Jeppsson, L. 2005. Conodont-based revisions of the late Ludfordian on Gotland, Sweden. GFF 127, 273-282.View article

Jeppsson, L. & Aldridge, R.J. 2000. Ludlow (late Silurian) oceanic episodes and events. Journal of the Geological Society, London 157, 1137-1148.View article

Jeppsson, L., Eriksson, M.E. & Calner, M. 2006. A latest Llandovery to latest Ludlow high-resolution biostratigraphy based on the Silurian of Gotland - a summary. GFF 128, 109-114.View article

Jeppsson, L., Talent, J.A., Mawson, R., Simpson, A.J., Andrew, A., Calner, M.,Whitford, D., Trotter, J.A., Sandström, O. & Caldon, H.J. 2007. High-resolution late Silurian correlations between Gotland, Sweden, and the Broken River region NE Australia: lithologies, conodonts and isotopes. Palaeogeography, Palaeoclimatology, Palaeoecology 245, 115-137.View article

Jeppsson, L., Viira, V. & Männik, P. 1994. Silurian conodontbased correlations between Gotland (Sweden) and Saaremaa (Estonia). Geological Magazine 131, 201-218.View article

Johnson, M.E. 1996. Stable cratonic sequences and a standard for Silurian eustasy. Geological Society of America Special Paper 306, 203-211.View article

Kaljo, D., Kiipli, T. & Martma, T. 1997. Carbon isotope event markers through the Wenlock-Pridoli sequence at Ohesaare (Estonia) and Priekule (Latvia). Palaeogeography, Palaeoclimatology, Palaeoecology 132, 211-223.View article

Kaljo, D., Kiipli, T. & Martma, T. 1998. Correlation of carbon isotope events and environmental cyclicity in the East Baltic Silurian. New York State Museum Bulletin 491, 297-312.

Kaljo, D.&Martma, T. 2006. Application of carbon isotope stratigraphy to dating Baltic Silurian rocks. GFF 128, 123-129.View article

Koren’, T.N. & Walliser, O.H. 1998. Stratigraphical ties between late Silurian graptolites and conodonts. Temas Geológico-Mineros Instituto Tecnológico Geominero de Espana 23, 248-251.

Kříž, J., Jaeger, H., Paris, F. & Schönlaub, H.P. 1986. Přídolí - the fourth subdivision of the Silurian. Jahrbuch der Geologischen Bundesanstalt 129, 291-360.

Laufeld, S. 1974. Silurian Chitinozoa from Gotland. Fossils and Strata 5, 1-130.

Lehnert, O., Frýda, J., Buggisch, W., Munnecke, A., Nützel, A., Kříž, J. & Manda, Š. 2007. ?13C records across the late Silurian Lau Event: new data from middle palaeolatitudes of northern peri-Gondwana. Palaeogeography, Palaeoclimatology, Palaeoecology 245, 227-244.View article

Loydell, D.K. 2007. Early Silurian positive ?13C excursions and their relationship to glaciations, sea-level changes and extinction events. Geological Journal 42, 531-546.View article

Loydell, D.K. In press. Graptolite biozone correlation charts. Geological Magazine.View article

Loydell, D.K. & Frýda, J. 2007. Carbon isotope stratigraphy of the upper Telychian and lower Sheinwoodian (Llandovery-Wenlock, Silurian) of the Banwy River section, Wales. Geological Magazine 144, 1015-1019.View article

Manda, Š., Štorch, P., Slavík, L., Frýda, J., Kříž, J. & Tasáryová, Z. In press. The graptolite, conodont and sedimentary record through the late Ludlow Kozlowskii Event (Silurian) in the shale-dominated succession of Bohemia. Geological Magazine.

Märss, T. & Miller, C.G. 2004. Thelodonts and distribution of associated conodonts from the Llandovery-lowermost Lochkovian of the Welsh Borderland. Palaeontology 47, 1211-1265.View article

Melchin, M.J. & Holmden, C. 2006. Carbon isotope chemostratigraphy of the Llandovery in Arctic Canada: implications for global correlation and sea-level change. GFF 128, 173-180.View article

Melchin, M.J., Koren’, T.N. & Štorch, P. 1998. Global diversity and survivorship patterns of Silurian graptolites. New York State Museum Bulletin 491, 165-182.

Miller, C.G. 1995. Ostracode and conodont distribution across the Ludlow/Přídolí boundary of Wales and the Welsh borderland. Palaeontology 38, 341-384.

Miller, C.G. & Märss, T. 1999. A conodont, thelodont and acanthodian fauna from the lower Přídolí (Silurian) of the Much Wenlock area, Shropshire. Palaeontology 42, 691-714.View article

Miller, C.G., Sutherland, S.J.E. & Dorning, K.J. 1997. Late Silurian (Ludlow-Přídolí) microfossils and sedimentation in the Welsh Basin near Clun, Shropshire. Geological Journal 32, 69-83.View article

Munnecke, A., Samtleben, C. & Bickert, T. 2003. The Ireviken Event in the lower Silurian of Gotland, Sweden - relation to similar Palaeozoic and Proterozoic events. Palaeogeography, Palaeoclimatology, Palaeoecology 195, 99-124.View article

Nestor, V. 2009. Biostratigraphy of the Ludlow chitinozoans from East Baltic drill cores. Estonian Journal of Earth Sciences 58, 170-184.View article

Noble, P.J., Zimmerman, M.K., Holmden, C. & Lenz, A.C. 2005. Early Silurian (Wenlockian) ?13C profiles from the Cape Phillips Formation, Arctic Canada and their relation to biotic events. Canadian Journal of Earth Sciences 42, 1419-1430.View article

Paris, F. & Kříž, J. 1984. Nouvelles espéces de Chitinozoaires a la limite Ludlow/Pridoli en Tchécoslovaquie. Review of Palaeobotany and Palynology 43, 155-177.View article

Richardson, J.B. & Rasul, S.M. 1990. Palynofacies in a late Silurian regressive sequence in the Welsh Borderland and Wales. Journal of the Geological Society, London 147, 675-686.View article

Siveter, D.J., Owens, R.M. & Thomas, A.T. 1989. Silurian field excursions: a geotraverse across Wales and the Welsh Borderland. 133 pp. National Museum of Wales, Cardiff.

Slavík, L., Kříž, J. & Carls, P. 2010. Reflection of the mid-Ludfordian Lau Event in conodont faunas of Bohemia. Bulletin of Geosciences 85, 395-414.View article

Smith, R.D.A. & Ainsworth, R.B. 1989. Hummocky cross-stratification in the Downton of the Welsh borderland. Journal of the Geological Society, London 146, 897-900.View article

Stricanne, L.,Munnecke, A. & Pross, J. 2006. Assessing mechanisms of environmental change: palynological signals across the late Ludlow (Silurian) positive isotope excursion (?13C, ?18O) on Gotland, Sweden. Palaeogeography, Palaeoclimatology, Palaeoecology 230, 1-31.View article

Sutherland, S.J.E. 1994. Ludlow chitinozoans from the type area and adjacent regions. Monograph of the Palaeontographical Society 148(594), 1-104, pls 1-18.

Urbanek, A. 1993. Biotic crises in the history of upper Silurian graptoloids: a palaeobiological model. Historical Biology 7, 29-50.View article

Urbanek, A. & Teller, L. 1997. Graptolites and stratigraphy of the Wenlock and Ludlow Series in the East European Platform. Palaeontologia Polonica 56, 23-57.

Verniers, J., Nestor, V., Paris, F., Dufka, P., Sutherland, S. & Van Grootel, G. 1995. A global Chitinozoa biozonation for the Silurian. Geological Magazine 132, 651-666.View article

Viira, V. & Aldridge, R.J. 1998. Upper Wenlock to lower Přídolí (Silurian) conodont biostratigraphy of Saaremaa, Estonia, and a correlation with Britain. Journal of Micropalaeontology 17, 33-50.View article

Wigforss-Lange, J. 1999. Carbon isotope 13C enrichment in Upper Silurian (Whitcliffian) marine calcareous rocks in Scania, Sweden. GFF 121, 273-279.View article

Woodcock, N.H., Awan, A., Johnson, T.E., Mackie, A.H. & Smith, R.D.A. 1988. Acadian tectonics of Wales during Avalonia/Laurentia convergence. Tectonics 7, 483-495.View article

Wrona, R. 1980. Upper Silurian-Lower Devonian Chitinozoa from the subsurface of southeastern Poland. Palaeontologia Polonica 41, 103-165.