Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-18T13:26:56.516Z Has data issue: false hasContentIssue false

Late Wenlock sequence stratigraphy in central England

Published online by Cambridge University Press:  28 July 2009

DAVID C. RAY*
Affiliation:
School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
CARLTON E. BRETT
Affiliation:
Department of Geology, University of Cincinnati, Cincinnati, OH 45221-0013, USA
ALAN T. THOMAS
Affiliation:
School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
ADRIAN V. J. COLLINGS
Affiliation:
Arup Geotechnics, The Arup Campus, Blythe Valley Business Park, Solihull, B90 8AE, UK
*
Author for correspondence: [email protected]

Abstract

The late Wenlock Series (Homerian Stage) of the northern Midland Platform (central England) comprises silty mudstones and limestones of the upper part of the Coalbrookdale and overlying Much Wenlock Limestone formations. Based on outcrop studies and borehole data, the sequence stratigraphical interpretation developed for the inliers of the West Midlands is slightly revised, and extended to the stratotype sections along Wenlock Edge. A single third-order cycle of sea-level change is identified, punctuated by a regressive–transgressive episode associated with a higher-order glacioeustatic cycle, allowing the upper Wenlock Series of the area to be divided into two subsequences (A and B). Subsequence A and the early transgressive systems tract began with regression associated with the basal sequence boundary in late Cyrtograptus lundgreni Biozone times. This was followed by a period of slow transgression or stillstand, allowing shallower water carbonate environments to prograde. A minor phase of regression followed, resulting in the generation of the shallowest water deposits of both the Lower Quarried Limestone and Farley members (of the Much Wenlock Limestone and Coalbrookdale formations, respectively). The overlying Subsequence B and the late transgressive systems tract are marked by transgression and a period of rapid sea-level fluctuation and are likely contained within the Gothograptus nassa Biozone. A minor highstand is widely recognizable at this time. The rest of Subsequence B consists of an initial phase of weak progradation (highstand systems tract), followed by a marked regression (falling stage systems tract) culminating in an erosive upper sequence boundary at or close to the top of the Monograptus ludensis Biozone, but within the uppermost Much Wenlock Limestone Formation. Above Subsequence B is a marked transgression into the Lower Elton Formation and the Ludlow Series. Both late Wenlock lowstands and the succeeding flooding events have been recognized on other palaeocontinents, reflecting the eustatic nature of sea-level changes reported here.

Type
Original Article
Copyright
Copyright © Cambridge University Press 2009

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

Aldridge, R. J., Siveter, David J., Siveter, Derek J., Lane, P. D., Palmer, D. C. & Woodcock, N. H. 2000. British Silurian stratigraphy. Peterborough: Geological Conservation Review Series, Joint Nature Conservation Committee, xviii + 542 pp.Google Scholar
Baarli, B. G., Johnson, M. E. & Antoshkina, A. I. 2003. Silurian stratigraphy and paleogeography of Baltica. In Silurian Lands and Seas, Paleogeography outside of Laurentia (eds Landing, E. & Johnson, M. E.), pp. 3–34. New York State Museum Bulletin no. 493.Google Scholar
Barclay, W. J., Davies, J. R., Humpage, A. J., Waters, R. A., Wilby, P. R., Williams, M. & Wilson, D. 2005. Geology of the Brecon district, a brief explanation of the geological map. Sheet explanation of the British Geological Survey, 1:50 000 Sheet 213, Brecon (England and Wales). Keyworth, Nottingham: British Geological Survey.Google Scholar
Bassett, M. G. 1974. Review of the stratigraphy of the Wenlock Series in the Welsh Borderland and South Wales. Palaeontology 17, 145–77.Google Scholar
Bassett, M. G. 1976. A critique of diachronism, community distributions and correlation of the Wenlock–Ludlow boundary. Lethaia 9, 207–18.Google Scholar
Bassett, M. G. 1989. The Wenlock Series in the Wenlock area. In A global standard for the Silurian System (eds Holland, C. H. & Bassett, M. G.), pp. 5173. Cardiff: National Museum of Wales, Geological Series no. 9.Google Scholar
Bassett, M. G., Cocks, L. R. M., Holland, C. H., Rickards, R. B. & Warren, P. T. 1975. The type Wenlock Series. Institute of Geological Sciences Report no. 75/13, 1–19.Google Scholar
Brett, C. E., Boucot, A. J. & Jones, B. 1993. Absolute depth limits of Silurian benthic assemblages. Lethaia 26, 2540.CrossRefGoogle Scholar
Brett, C. E., Ferretti, A., Histon, K. & Schönlaub, H.-P. 2007. Eustasy and basin dynamics of the Silurian of the Carnic Alps (Austria). Acta Palaeontologica Sinica 46, 43–9.Google Scholar
Butler, A. J. 1939. The stratigraphy of the Wenlock Limestone at Dudley. Quarterly Journal of the Geological Society of London 95, 3474.Google Scholar
Calner, M. 1999. Stratigraphy, facies development, and depositional dynamics of the Late Wenlock Fröjel Formation, Gotland, Sweden. Geologiska Föreningens i Stockholm förhandlingar 121, 1324.Google Scholar
Calner, M. 2005. Silurian carbonate platforms and extinction events – ecosystem changes exemplified from Gotland, Sweden. Facies 51, 584–91.Google Scholar
Calner, M. 2008. Silurian global events – at the tipping point of climate change. In Mass extinctions (ed. Elewa, A. M. T.), pp. 2158. Berlin and Heidelberg: Springer-Verlag.CrossRefGoogle Scholar
Calner, M. & Jeppsson, L. 2002. Carbonate platform evolution and conodont stratigraphy during the middle Silurian Mulde Event, Gotland, Sweden. Geological Magazine 140, 173203.Google Scholar
Calner, M., Jeppsson, L. & Eriksson, M. J. 2004. Ytterholmen revisited – implications for the Later Wenlock stratigraphy of Gotland and coeval extinctions. Geologiska Föreningens i Stockholm förhandlingar 126, 231–41.Google Scholar
Calner, M. & Säll, E. 1999. Transgressive oolites onlapping a Silurian rocky shoreline unconformity, Gotland, Sweden. Geologiska Föreningens i Stockholm förhandlingar 121, 91100.Google Scholar
Caputo, M. V. 1998. Ordovician–Silurian glaciations and global sea-level changes. In Silurian cycles: Linkages of Dynamic Stratigraphy with Atmospheric, Oceanic, and Tectonic Changes (eds Landing, E. & Johnson, M. E.), pp. 15–25. New York State Museum Bulletin no. 491.Google Scholar
Cherns, L., Cocks, L. R. M., Davies, J. R., Hillier, R. D., Waters, R. A. & Williams, M. 2006. Silurian: the influence of extensional tectonics and sea-level changes on sedimentation in the Welsh Borderland and on the Midland Platform. In The Geology of England and Wales, 2nd ed. (eds Brenchley, P. J. & Rawson, P. F.), pp. 75102. London: The Geological Society.Google Scholar
Collings, A. V. J. 1989. A major regressive event at the top of the Much Wenlock Limestone Formation in the West Midlands. The Murchison Symposium; An International Symposium on The Silurian System. Program and Abstracts, p. 40.Google Scholar
Corfield, R. M., Siveter, Derek J., Cartlidge, J. E. & McKerrow, W. S. 1992. Carbon isotope excursions near the Wenlock–Ludlow (Silurian) boundary in the Anglo-Welsh area. Geology 20, 371–4.Google Scholar
Cramer, B. S., Kleffner, M. A. & Saltzman, M. R. 2006. The Late Wenlock Mulde positive carbon isotope excursion in North America. Geologiska Föreningens i Stockholm förhandlingar 128, 8590.Google Scholar
Dorning, K. J. 1983. Palynology and stratigraphy of the Much Wenlock Limestone Formation of Dudley, Central England. Mercian Geologist 9, 3140.Google Scholar
Dorning, K. J. & Bell, D. G. 1987. The Silurian shelf microfacies: acritarch distribution in the Much Wenlock Limestone Formation. In Micropalaeontology of carbonate environments (ed. Hart, M. B.), pp. 266–87. Chichester: Ellis Horwood Ltd.Google Scholar
Dorning, K. J. & Harvey, C. 1999. Wenlock cyclicity, palynology, and stratigraphy in the Buildwas, Coalbrookdale, and Much Wenlock Limestone formations, Shropshire, England. Bollettino della Societa Paleontologica Italia 38, 155–66.Google Scholar
Haq, B. U. & Schutter, S. R. 2008. A chronology of Paleozoic sea-level change. Science 322, 64–8.CrossRefGoogle Scholar
Hurst, J. M. 1975. The diachronism of the Wenlock Limestone. Lethaia 8, 301–14.CrossRefGoogle Scholar
Johnson, M. E. 2006. Relationship of Silurian sea-fluctuations to oceanic episodes and events. Geologiska Föreningens i Stockholm förhandlingar 128, 115–21.Google Scholar
Kaljo, D. & Martma, T. 2006. Application of carbon isotope stratigraphy to dating the Baltic Silurian rocks. Geologiska Föreningens i Stockholm förhandlingar 128, 123–9.Google Scholar
Kemp, A. E. S. 1991. Mid-Silurian pelagic and hemipelagic sedimentation and palaeoceanography. In The Murchison Symposium: Proceedings of an International Symposium on the Silurian System (eds Bassett, M. G. et al. ), pp. 261–99. Special Papers in Palaeontology 44.Google Scholar
Lawson, J. D. 1955. The geology of the May Hill Inlier. Quarterly Journal of the Geological Society of London 111, 85116.Google Scholar
Lenz, A. C., Noble, P. J., Masiak, M., Poulson, S. R. & Kozłowska, A. 2006. The lundgreni Extinction Event: integration of paleontological and geochemical data from Arctic Canada. Geologiska Föreningens i Stockholm förhandlingar 128, 153–8.Google Scholar
Loydell, D. K. 1998. Early Silurian sea-level changes. Geological Magazine 135, 447–71.Google Scholar
Loydell, D. K. & Fone, W. 1998. Graptolites from the Lower Elton Formation (Ludlow) of Shadwell Rock Quarry, Shropshire. Geological Journal 33, 147–8.Google Scholar
McLaughlin, P. I. & Brett, C. E. 2007. Signatures of sea-level rise on the carbonate margin of a Late Ordovician Foreland Basin: a case study from the Cincinnati Arch, USA. Palaios 22, 245–67.Google Scholar
Miller, K. G., Kominz, M. A., Browning, J. V., Wright, J. D., Mountain, G. S., Katz, M. E., Sugarman, P. J., Cramer, B. S., Christie-Blick, N. & Pekar, S. F. 2005. The Phanerozoic record of global sea-level change. Science 310, 1293–8.CrossRefGoogle ScholarPubMed
Murchison, R. I. 1872. Siluria. The history of the oldest known rocks containing organic remains, with a brief description of the distribution of gold over the Earth, 5th ed. London: John Murray, xvi + 523 pp.Google Scholar
Pocock, R. W., Whitehead, T. A., Wedd, C. B. & Robertson, T. 1938. Shrewsbury district, including the Hanwood Coalfield. Memoir of the Geological Survey of Great Britain. HMSO: London, xii + 297 pp.Google Scholar
Ratcliffe, K. T. 1988. Oncoids as environmental indicators in the Much Wenlock Limestone Formation of the English Midlands. Journal of the Geological Society, London 145, 117–24.Google Scholar
Ratcliffe, K. T. & Thomas, A. T. 1999. Carbonate depositional environments in the late Wenlock of England and Wales. Geological Magazine 136, 189204.Google Scholar
Ray, D. C. & Thomas, A. T. 2007. Carbonate depositional environments, sequence stratigraphy and exceptional skeletal preservation in the Much Wenlock Limestone Formation (Silurian) of Dudley, England. Palaeontology 50, 197222.CrossRefGoogle Scholar
Ross, R. J., Naeser, C. W., Izett, G. A., Obradovich, J. D., Bassett, M. G., Hughes, C. P., Cocks, L. R. M., Dean, W. T., Ingham, J. K., Jenkins, C. J., Rickards, R. B., Sheldon, P. R., Toghill, P., Whittington, H. B. & Zalasiewicz, J. 1982. Fission-track dating of British Ordovician and Silurian stratotypes. Geological Magazine 119, 135–53.Google Scholar
Schofield, D. I., Davies, J. R., Jones, N. S., Leslie, A. B., Waters, R. A., Williams, M., Wilson, D., Venus, J. & Hillier, R. D. 2009. Geology of the Llandovery district, a brief explanation of the geological map. Sheet Explanation of the British Geological Survey, 1:50000 Sheet 212, Llandovery (England and Wales). Keyworth, Nottingham: British Geological Survey.Google Scholar
Schofield, D. I., Davies, J. R., Waters, R. A., Wilby, P. R., Williams, M. & Wilson, D. 2004. Geology of the Builth Wells district, a brief explanation of the geological map. Sheet Explanation of the British Geological Survey, 1:50000 Sheet 196 Builth Wells (England and Wales). Keyworth, Nottingham: British Geological Survey.Google Scholar
Scoffin, T. P. 1971. The conditions of growth of the Wenlock reefs of Shropshire (England). Sedimentology 17, 173219.Google Scholar
Shergold, J. H. & Bassett, M. G. 1970. Facies and faunas at the Wenlock/Ludlow boundary of Wenlock Edge, Shropshire. Lethaia 3, 113–42.CrossRefGoogle Scholar
Siveter, David J., Owens, R. M. & Thomas, A. T. 1989. Silurian field excursions: a geotraverse across Wales and the Welsh Borderlands, pp. 2335. Cardiff: National Museum of Wales, Geological Series no. 10.Google Scholar
White, D. E. 1974. The boundary between the Wenlock and Ludlow Series. Geological Magazine 111, 448–9.Google Scholar
Woodcock, N. H., Butler, A. J., Davies, J. R. & Waters, R. A. 1996. Sequence stratigraphical analysis of late Ordovician and early Silurian depositional systems in the Welsh Basin: a critical assessment. In Sequence Stratigraphy in British Geology (eds Hesselbo, S. & Parkinson, N.), pp. 197208. Geological Society of London, Special Publication no. 103.Google Scholar