Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-28T16:15:28.298Z Has data issue: false hasContentIssue false
  • English
  • Français

Chronometric calibration of mid-Ordovician to Tournaisian conodont zones: a compilation from recent graphic-correlation and isotope studies

Published online by Cambridge University Press:  01 May 2009

Barry G. Fordham
Barry G. Fordham
Affiliation:
Geological Survey of Queensland, G.P.O. Box 194, Brisbane, Queensland 4001, Australia
Get access Rights & Permissions [Opens in a new window]

Abstract

Three available graphic-correlation analyses are used to calibrate mid-Palaeozoic conodont zonations: Sweet's scheme for the mid- to Upper Ordovician; Kleffner's for the mid- to Upper Silurian; and Murphy & Berry's for the lower and middle Lower Devonian. The scheme of Sweet is scaled by applying the high-precision U-Pb zircon date of Tucker and others for the Rocklandian and linked with that of Kleffner by scaling the graptolite sequence of the Ordovician-Silurian global stratotype section to fit two similarly derived dates from this sequence. The top of Kleffner's scheme, all of Murphy & Berry's, as well as standard zones to the Frasnian are calibrated by using tie-points of the latest Cambridge-BP time-scale (GTS 89). However, the recent microbeam zircon date by Claoué-Long and others for the Hasselbachtal Devonian-Carboniferous auxiliary stratotype is used to calibrate the standard Famennian zones. Also the similarly derived but preliminary determination reported by Roberts and others from the Isismurra Formation of New South Wales is tentatively taken as the top of the Tournaisian and so used to calibrate Tournaisian zones. Despite the considerable extrapolation required to compile these schemes and their inherent errors, the resultant time-scale closely agrees with other dates of Tucker and others from the Llanvirn as well as the GTS 89 Homerian-Gorstian tie-point. This suggests that stratigraphic methods can be usefully applied to geochronometry. The Llandovery appears to have lasted longer (16 m. y.) than usually envisaged and the Ordovician-Silurian boundary may need to be lowered to approximately 443.5 Ma. Certainly, chrons varied widely in duration and further stratigraphic studies to estimate their relative durations as well as high-resolution dating for their calibration will be crucial to more accurate biochronometries.

Type
Articles
Information
Geological Magazine , Volume 129 , Issue 6 , November 1992 , pp. 709 - 721
Copyright
Copyright © Cambridge University Press 1992

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. 1972. Llandovery conodonts from the Welsh Borderland. Bulletin of the British Museum (Natural History), Geology 22, 125–231, 9 pls.Google Scholar
Barnes, C. R. & Bergström, S. M. 1988. Conodont biostratigraphy of the uppermost Ordovician and lowermost Silurian. Bulletin of the British Museum (Natural History), Geology 43, 325–43.Google Scholar
Barnes, C. R. & Williams, S. H. 1988. Conodonts from the Ordovician-Silurian boundary stratotype, Dob's Linn, Scotland. Bulletin of the British Museum (Natural History), Geology 43, 31–9.Google Scholar
Barrick, J. E. & Klapper, G. 1976. Multielement Silurian (late Llandoverian-Wenlockian) conodonts of the Clarita Formation, Arbuckle Mountains, Oklahoma, and phylogeny of Kockelella. Geologica et Palaeontologica 10, 59–100.Google Scholar
Bassett, D. A., Whittington, H. B. & Williams, A. 1966. The stratigraphy of the Bala district, Merionethshire. Quarterly Journal of the Geological Society of London 122, 219–71, pl.CrossRefGoogle Scholar
Becker, T. 1988. Ammonoids from the Devonian-Carboniferous boundary in the Hasselbach Valley (northern Rhenish Slate Mountains). Courier Forschungsinstitut Senckenberg 100, 193–213.Google Scholar
Becker, T., Bless, M. J. M., Brauckmann, C, Friman, L., Higgs, K., Keupp, H., Korn, D., Langer, W., Paproth, E., Racheboeuf, P., Stoppel, D., Steel, M. & Zakowa, H. 1984. Hasselbachtal, the section best displaying the Devonian-Carboniferous boundary beds in the Rhenish Massif (Rheinisches Schiefergebirge). Courier Forschungsinstitut Senckenberg 67, 181–91.Google Scholar
Bergström, S. M. 1971. Conodont biostratigraphy of the Middle and Upper Ordovician of Europe and eastern North America. Geological Society of America, Memoir 127, 83–161.CrossRefGoogle Scholar
Bergström, S. M. 1983. Biogeography, evolutionary relationships, and biostratigraphic significance of Ordovician platform conodonts. Fossils and Strata 15, 35–58.CrossRefGoogle Scholar
Bergström, S. M. & Mitchell, C. E. 1986. The graptolite correlation of the North American Upper Ordovician Standard. Lethaia 19, 247–66.CrossRefGoogle Scholar
Bergström, S. M., Rhodes, F. H. T. & Lindström, M. 1987. Conodont biostratigraphy of the Llandvirn-Llandeilo and Llandeilo-Caradoc Series boundaries in the Ordovician System of Wales and the Welsh Borderland. In Conodonts: Investigative Techniques and Applications (ed. Austin, R. L.), pp. 294–315. Chichester: Ellis Horwood.Google Scholar
Bischoff, G. C. O. 1957. Die Conodonten-Stratigraphie des rheno-herzynischen Unterkarbons mit Berücksichtigung der Wocklumeria-Stufe und der Devon/Karbon-Grenze. Abhandlungen des Hessischen Landesamtes für Bodenforschung 19, 64 pp., 6 pls.Google Scholar
Bischoff, G. C. O. 1986. Early and middle Silurian conodonts from midwestern New South Wales. Courier Forschungsinstitut Senckenberg 89, 337 pp.Google Scholar
Boucot, A. J. 1975. Evolution and Extinction Rate Controls. Amsterdam: Elsevier, 427 pp.Google Scholar
Brower, J. C. & Bussey, D. T. 1985. A comparison of five quantitative techniques for biostratigraphy. In Quantitative Stratigraphy (eds Gradstein, F. M., Agterberg, F. P., Brower, J. C. and Schwarzacher, W. S.), pp. 279–306. Paris: UNESCO.Google Scholar
Churkin, M. Jr., Carter, C. & Johnson, B. R. 1977. Subdivision of Ordovician and Silurian time scale using accumulation rates of graptolitic shale. Geology 5, 452–6.2.0.CO;2>CrossRefGoogle Scholar
Claoué-Long, J. C., Jones, P. J. & Roberts, J. in press. The age of the Devonian-Carboniferous boundary. Annales de la Société géologique de Belgique.Google Scholar
Claoué-Long, J. C., Jones, P. J., Roberts, J. & Maxwell, S. 1990. SHRIMP determination of the age of the Devonian-Carboniferous boundary. Abstracts, Geological Society of Australia 27, 20.Google Scholar
Claoué-Long, J. C., Jones, P. J., Roberts, J. & Maxwell, S. 1992. The numerical age of the Devonian-Carboniferous boundary. Geological Magazine 129, 281–91.CrossRefGoogle Scholar
Claoué-Long, J. C., Jones, P. J. & Truswell, E. M. 1989. Calibration of the Phanerozoic time scale: a pilot study towards accurate dating of Phanerozoic biozones. In BMR Research Symposium 1989, 7 pp. Canberra: Bureau of Mineral Resources, Australia.Google Scholar
Collinson, C. Scott, A. J. & Rexroad, C. B. 1962. Six charts showing biostratigraphic zones, and correlations based on conodonts from the Devonian and Mississippian rocks of the upper Mississippi Valley. Illinois Geological Survey, Circular 328, 32 pp.Google Scholar
Cooper, B. J. 1975. Multielement conodonts from the Brassfield Limestone (Silurian) of southern Ohio. Journal of Paleontology 49, 984–1008.Google Scholar
Edwards, L. E. 1984. Insights on why graphic correlation (Shaw's method) works. Journal of Geology 92, 583–97.CrossRefGoogle Scholar
Edwards, L. E. 1985. Insights on why graphic correlation (Shaw's method) works:a reply. Journal of Geology 93, 507–9.CrossRefGoogle Scholar
Edwards, L. E. 1989. Supplemented graphic correlation: a powerful tool for paleontologists and non-paleontologists. Palaios 4, 127–43.CrossRefGoogle Scholar
Fåhræus, L. E. 1971. Lower Devonian conodonts from the Michelle and Prongs Creek Formations, Yukon Territory. Journal of Paleontology 45, 665–83.Google Scholar
Gradstein, F. M. 1985. Ranking and scaling in exploration micropaleontology. In Quantitative Stratigraphy (eds Gradstein, F. M., Agterberg, F. P., Brower, J. C. and Schwarzacher, W. S.), pp. 109–60. Paris: UNESCO.Google Scholar
Gradstein, F. M. & Agterberg, F. P. 1985. Quantitative correlation in exploration micropaleontology. In Quantitative stratigraphy (eds Gradstein, F. M., Agterberg, F. P., Brower, J. C. and Schwarzacher, W. S.), pp. 309–357. Paris: UNESCO.Google Scholar
Groessens, E. 1974. Distribution de conodontes dans le Dinantian de la Belgique. In Namur 1974. International Symposium on Belgian Micropaleontological Limits from Emsian to Visean, Publication 17 (eds Bouckaert, J. and Streel, M.), 193 pp. Brussels: Geological Survey of Belgium.Google Scholar
Groos-Uffenorde, H. & Uffenorde, H. 1974. Zur Mikrofauna im höchsten Oberdevon und tiefen Unterkarbon im nördlichen Sauerland (Conodonta, Ostracoda, Rheinisches Schiefergebirge). Notizblatt des Hessischen Landesamtes für Bodenforschung zu Wiesbaden 102, 58–87.Google Scholar
Harland, W. B., Armstrong, R. L., Cox, A. V., Craig, L. E., Smith, A. G. & Smith, D. G. 1990. A Geologie Time Scale 1989. Cambridge: University Press, 263 pp.Google Scholar
Harper, C. W. & Crowley, K. D. 1985. Insights on why graphic correlation (Shaw's method) works: a discussion. Journal of Geology 93, 503–6.CrossRefGoogle Scholar
Higgs, K. & Streel, M. 1984. Spore stratigraphy at the Devonian-Carboniferous boundary in the northern ‘Rheinisches Schiefergebirge’, Germany. Courier Forschungsinstitut Senckenberg 67, 157–79.Google Scholar
Johnson, J. G. 1990. Lower and Middle Devonian brachio-pod-dominated communities of Nevada, and their position in a biofacies-province-realm model. Journal of Paleontology 64, 902–41.CrossRefGoogle Scholar
Johnson, J. G., Klapper, G. & Sandberg, C. A. 1985. Devonian eustatic fluctuations in Euramerica. Geological Society of America Bulletin 96, 567–87.2.0.CO;2>CrossRefGoogle Scholar
Johnson, M. E. & Worsley, D. 1982. Chronology and depositional environments of Early Silurian sequences in the Oslo region. In International Union of Geological Sciences, Subcommission on Silurian Stratigraphy, Field Meeting, Oslo region, 1982 (ed. Worsley, D.) (Paleontological Contributions from the University of Oslo 278), pp. 149–60. Oslo: Paleontologisk Museum, Oslo.Google Scholar
Jones, O. T. 1909. The Hartfell-Valentian succession in the district around Plynlimon and Pont Erwyd (North Cardiganshire). Quarterly Journal of the Geological Society of London 65, 463–537.CrossRefGoogle Scholar
Jones, O. T. 1925. The geology of the Llandovery district: Part I - the southern area. Quarterly Journal of the Geological Society of London 81, 344–88, pl.CrossRefGoogle Scholar
Jones, P. J. 1988. Comments on some Australian, British and German isotopic age data for the Carboniferous System. I.U.G.S. Subcommission on Carboniferous Stratigraphy Newsletter on Carboniferous Stratigraphy 6, 26–9.Google Scholar
Jones, P. J. 1991. Australian Phanerozoic Timescales, 5. Carboniferous. Biostratigraphic Chart and Explanatory Notes. Bureau of Mineral Resources, Australia, Record 1989/35, 43 pp., 3 charts.Google Scholar
Jones, R. K., Brooks, M., Bassett, M. G., Austin, R. L. & Aldridge, R. J. 1969. An upper Llandovery limestone overlying Hollybush Sandstone (Cambrian) in Holly-bush Quarry, Malvern Hills. Geological Magazine 106, 457–69.CrossRefGoogle Scholar
Klapper, G. (With Johnson, D. B.). 1977. Lower and Middle Devonian conodont sequence in central Nevada. In Western North America: Devonian (eds Murphy, M. A., Berry, W. B. N. and Sandberg, C. A.), pp. 33–54. Riverside: University of California (Campus Museum Contribution 4).Google Scholar
Klapper, G. 1989. The Montagne Noire Frasnian (Upper Devonian) conodont succession. Canadian Society of Petroleum Geologists, Memoir 14, 449–68.Google Scholar
Klapper, G. & Johnson, J. G. 1980. Endemism and dispersal of Devonian conodonts. Journal of Paleontology 54, 400–55.Google Scholar
Klapper, G. & Murphy, M. A. 1975. Silurian-Lower Devonian conodont sequence in the Roberts Mountains Formation of central Nevada. University of California Publications in Geological Sciences 111, 62 pp., 8 tables, 12 pls.Google Scholar
Klapper, G. & Murphy, M. A. 1980. Conodont zonal species from the delta and pesavis Zones (Lower Devonian) in central Nevada. Neues Jahrbuch für Geologie und Paläontologie, Monatshefte 1980, 490–504.CrossRefGoogle Scholar
Klapper, G., Sandberg, C. A., Collinson, C., Huddle, J. W., Orr, R. W., Rickard, L. V., Schumacher, D., Seddon, G. & Uyeno, T. T. 1971. North American Devonian conodont biostratigraphy. Geological Society of America, Memoir 127, 285–316.CrossRefGoogle Scholar
Klapper, G. & Ziegler, W. 1979. Devonian conodont biostratigraphy. Special Papers in Palaeontology 23, 199–224.Google Scholar
Kleffner, M. A. 1989. A conodont-based Silurian chronostratigraphy. Geological Society of American Bulletin 101, 904–12.2.3.CO;2>CrossRefGoogle Scholar
Kunk, M. J. & Sutter, J. F. 1984. 40Ar/39Ar age spectrum dating of biotite from middle Ordovician bentonites, eastern North America. In Aspects of the Ordovician System (ed. Bruton, D. L.) (Palaeontological Contributions from the University of Oslo 295), pp. 11–22. Oslo: Universitetsforlaget.Google Scholar
Lane, H. R. & Ormiston, A. R. 1979. Siluro-Devonian biostratigraphy of the Salmontrout River area, east-central Alaska. Geologica et Palaeontologica 13, 39–96.Google Scholar
Lane, H. R., Sandberg, Ca. & Ziegler, W. 1980. Taxonomy and phylogeny of some Lower Carboniferous conodonts and preliminary standard post-Siphonodella zonation. Geologica et Palaeontologica 14, 117–64.Google Scholar
Lapworth, C. 1878. The Moffat Series. Quarterly Journal of the Geological Society of London 34, 240–346, 3 pls.CrossRefGoogle Scholar
Lapworth, H. 1900. The Silurian sequence of Rhayader. Quarterly Journal of the Geological Society of London 56, 67–137.CrossRefGoogle Scholar
McCracken, A. D. & Barnes, C. R. 1981. Conodont biostratigraphy and paleoecology of the Ellis Bay Formation, Anticosti Island, Quebec, with special reference to Late Ordovician-Early Silurian chrono-stratigraphy and the Systemic boundary. Geological Survey of Canada, Bulletin 329, 51–134.Google Scholar
Marr, J. E. & Nicholson, H. A. 1888. The Stockdale Shales. Quarterly Journal of the Geological Society of London 44, 654–732.CrossRefGoogle Scholar
Matti, J. C., Murphy, M. A. & Finney, S. C. 1975. Silurian and Lower Devonian basin and basin-slope limestones, Copenhagen Canyon, Nevada. Geological Society of America, Special Paper 159, 48 pp.Google Scholar
Miller, F. X. 1977. The graphic correlation method in biostratigraphy. In Concepts and Methods of Biostratigraphy (eds Kaufman, E. G. and Hazel, J. E.), pp. 165–86. Stroudsburg, PA: Dowden, Hutchinson and Ross.Google Scholar
Murphy, M. A. 1987. The possibility of a Lower Devonian equal-increment time scale based on lineages in Lower Devonian conodonts. In Investigative Techniques and Applications (ed. Austin, R. L.), pp. 284–93. Chichester: Ellis Horwood.Google Scholar
Murphy, M. A. & Berry, W. B. N. 1983. Early Devonian conodont-graptolite collation and correlations with brachiopod and coral zones, central Nevada. Bulletin, American Association of Petroleum Geologists 67, 371–9.Google Scholar
Murphy, M. A. & Edwards, L. E. 1977. The Silurian-Devonian boundary in central Nevada. In Western North America: Devonian (eds Murphy, M. A., Berry, W. B. N. and Sandberg, C. A.), pp. 183–9. Riverside: University of California (Campus Museum Contribution 4).Google Scholar
Nakrem, H. A. 1986. Llandovery conodonts from the Oslo region, Norway. Norsk Geologisk Tidsskrift 66, 121–33.Google Scholar
Nemec, W. 1988. Coal correlations and intrabasinal subsidence: a new analytical perspective. In New Perspectives in Basin Analysis (eds Kleinspehn, K. L. and Paola, C.), pp. 161–88. New York: Springer-Verlag.CrossRefGoogle Scholar
Nicoll, R. S. & Rexroad, C. B. 1969. Stratigraphy and conodont paleontology of the Salamonie Dolomite and Lee Creek Member of the Brassfield Limestone (Silurian) in southeastern Indiana and adjacent Kentucky. Indiana Geological Survey, Bulletin 40, 73 pp., 7 pls.Google Scholar
Nowlan, G. S. 1983. Early Silurian conodonts of eastern Canada. Fossils and Strata 15, 95–110.CrossRefGoogle Scholar
Odin, G. S. & Gale, N. H. 1982. Numerical dating of Hercynian times (Devonian to Permian). In Numerical Dating in Stratigraphy (ed. Odin, G. S.), pp. 487–500. Chichester: John Wiley.Google Scholar
Paproth, E. 1989. Working Group on the Devonian-Carboniferous boundary. I.U. G. S. Subcommission on Carboniferous Stratigraphy Newsletter on Carboniferous Stratigraphy 7, 18.Google Scholar
Roberts, J. 1965. Lower Carboniferous zones and correlation based on faunas from the Gresford-Dungog district, New South Wales. Journal of the Geological Society of Australia 12, 105–22.CrossRefGoogle Scholar
Roberts, J., Claoué-Long, J. C. & Jones, P. J. 1991 a. Calibration of the Carboniferous and Early Permian of the southern New England Orogen by SHRIMP ion microprobe zircon analyses. In Twenty-fifth Newcastle Symposium on ‘Advances in the study of the Sydney Basin’ (ed. Diessel, C. F. K.), pp. 38–43. Newcastle: Department of Geology, University of Newcastle (Publication 413).Google Scholar
Roberts, J., Claoué-Long, J. C. & Jones, P. J. 1991 b. Calibration of the Carboniferous and Early Permian of the southern New England Orogen by SHRIMP ion microprobe zircon analyses. I.U.G.S. Subcommission on Carboniferous Stratigraphy Newsletter on Carboniferous Stratigraphy 9, 15–17.Google Scholar
Ross, R. J. Jr., 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.CrossRefGoogle Scholar
Sandberg, C. A. 1980. Utility of conodonts in determining rates of synorogenic sedimentation and in timing Antler Orogenic events, western United States. Abhundlungen der Geologischen Bundesanstalt 35, 209.Google Scholar
Sandberg, C. A. & Gutschick, R. C. 1979. Guide to conodont biostratigraphy of Upper Devonian and Mississippian rocks along the Wasatch Front and Cordilleran hingeline, Utah. Brigham Young University Geology Studies 26(3), 107–33.Google Scholar
Sandberg, C. A., Gutschick, R. C., Johnson, J. G., Poole, F. G. & Sando, W. J. 1983. Middle Devonian to Late Mississippian geologic history of the Overthrust Belt region, western United States. In Geologic Studies of the Cordilleran Thrust Belt (ed. Powers, R. B.), pp. 691–719. Denver, CO: Rocky Mountain Association of Geologists.Google Scholar
Sandberg, C. A., Gutschick, R. C., Johnson, J. G., Poole, F. G. & Sando, W. J. 1986. Middle Devonian to late Mississippian event stratigraphy of Overthrust Belt region, western United States. Annales de la Société géologique de Belgique 109, 205–7.Google Scholar
Sandberg, C. A. & Poole, F. G. 1977. Conodont biostratigraphy and depositional complexes of Upper Devonian cratonic-platform and continental-shelf rocks in the western United States. In Western North America:Devonian (eds Murphy, M. A., Berry, W. B. N. and Sandberg, C. A.), pp. 144–82. Riverside: University of California (Campus Museum Contribution 4).Google Scholar
Sandberg, C. A., Ziegler, W. & Bultynck, P. 1989. New standard conodont zones and early Ancyrodella phylogeny across Middle-Upper Devonian boundary. Courier Forschungsinstitut Senckenberg 110, 195–230.Google Scholar
Sandberg, C. A., Ziegler, W., Leuteritz, K. & Brill, S. M. 1978. Phylogeny, speciation, and zonation of Siphonodella (Conodonta, Upper Devonian and Lower Carboniferous). Newsletter on Stratigraphy 7, 102–20.CrossRefGoogle Scholar
Shaw, A. B. 1964. Time in Stratigraphy. New York: McGraw-Hill, 365 pp.Google Scholar
Shaw, A. B. 1974. Integration of biostratigraphical information from numerous sequences. In Marine Plankton and Sediments and Third Planktonic Conference (ed. Seibold, E.), p. 80. Paris: International Council of Scientific Unions, UNESCO.Google Scholar
Strusz, D. L. 1989. Australian Phanerozoic Timescales, 3. Silurian. Biostratigraphic Chart and Explanatory Notes. Bureau of Mineral Resources, Australia, Record 1989/33, 28 pp, 3 pls.Google Scholar
Sweet, W. C. 1979. Late Ordovician conodonts and biostratigraphy of the western Midcontinent Province. Brigham Young University Geology Studies 26, (3), 45–85.Google Scholar
Sweet, W. C. 1984. Graphic correlation of upper Middle and Upper Ordovician rocks, North American Mid-continent Province, U.S.A. In Aspects of the Ordovician System (ed. Bruton, D. L.) (Palaeontological Contributions from the University of Oslo 295), pp. 23–35. Oslo: Universitetsforlaget.Google Scholar
Sweet, W. C. 1988. Mohawkian and Cincinnatian chrono-stratigraphy. New York State Museum Bulletin 462, 84–90.Google Scholar
Sweet, W. C., Ethington, R. L. & Barnes, C. R. 1971. North American Middle and Upper Ordovician conodont faunas. Geological Society of America, Memoir 127, 163–93.CrossRefGoogle Scholar
Tucker, R. D., Krogh, T. E., Ross, R. J. Jr. & Williams, S. H. 1990. Time-scale calibration by high-precision U-Pb zircon dating of interstratified volcanic ashes in the Ordovician and Lower Silurian stratotypes of Britain. Earth and Planetary Science Letters 100, 51–8.CrossRefGoogle Scholar
Uyeno, T. T. & Barnes, C. R. 1983. Conodonts of the Jupiter and Chicotte Formations (Lower Silurian), Anticosti Island, Québec. Geological Survey of Canada, Bulletin 355, 49 pp.Google Scholar
Voges, A. 1959. Conodonten aus dem Untercarbon I und II (Gattendorfia- und Pericyclus-Stufe) des Sauerlandes. Paläontologische Zeitschrift 33, 266–314, 3 pls.CrossRefGoogle Scholar
Voges, A. 1960. Die Bedeutung der Conodonten für die Stratigraphie des Unterkarbons I und II (Gattendorfia- und Pericyclus-Stufe) im Sauerland. Fortschritte in der Geologie von Rheinland und Westfalen 3, (1), 197–228.Google Scholar
Walliser, O. H. 1964. Conodonten des Silurs. Abhandlungen des Hessischen Landesamtes für Bodenforschung 41, 106 pp., 32 pls.Google Scholar
Webby, B. D. & Nicoll, R. S. 1989. Australian Phanerozoic Timescales, 2. Ordovician, Biostratigraphic Chart and Explanatory Notes. Bureau of Mineral Resources, Australia, Record 1989/32, 42 pp., 1 chart.Google Scholar
Williams, S. H. 1980. An excursion guide to Dob's Linn. Proceedings of the Geological Society of Glasgow 121/122, 13–18.Google Scholar
Williams, S. H. 1982 a. Upper Ordovician graptolites from the top Lower Hartfell Shale Formation (D. clingani and P. linearis Zones) near Moffat, southern Scotland. Transactions of the Royal Society of Edinburgh, Earth Sciences 72, 229–55.CrossRefGoogle Scholar
Williams, S. H. 1982 b. The Late Ordovician graptolite 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
Wood, E. M. R. 1906. On the Tarannon Series of Tarannon. Quarterly Journal of the Geological Society of London 62, 644–701.CrossRefGoogle Scholar
Young, G. C. 1989. Australian Phanerozoic Timescales, 4. Devonian. Biostratigraphic Chart and Explanatory Notes. Bureau of Mineral Resources, Australia, Record 1989/34, 17 pp., 1 chart.Google Scholar
Ziegler, W. 1962. Taxonomie und Phylogenie Oberdevonischer Conodonten und ihre stratigraphische Bedeutung. Abhandlungen des Hessischen Landesamtes für Bodenforschung 38, 166 pp., 14 pls.Google Scholar
Ziegler, W. 1971. Conodont stratigraphy of the European Devonian. Geological Society of America, Memoir 127, 227–84.CrossRefGoogle Scholar
Ziegler, W. 1978. Devonian. In Contributions to the Geologic Time Scale (eds Cohee, G. V., Glaessner, M. F. and Hedberg, H. D.), pp. 337–9. Tulsa, OK: American Association of Petroleum Geologists.Google Scholar
Ziegler, W. & Klapper, G. 1982. The disparilis conodont Zone, the proposed level for the Middle-Upper Devonian boundary. Courier Forschungsinstitut Senckenberg 55, 463–92.Google Scholar
Ziegler, W. & Klapper, G. 1985. Stages of the Devonian System. Episodes 8, 104–9.CrossRefGoogle Scholar
Ziegler, W. & Sandberg, C. A. 1983. Palmatolepis-based revision of upper part of standard Late Devonian conodont zonation. Geological Society of America, Abstracts with Programs 15 (4), 221.Google Scholar
Ziegler, W. & Sandberg, C. A. 1984. Palmatolepis-based revision of upper part of standard Late Devonian conodont zonation. Geological Society of America, Special Papers 196, 179–94.CrossRefGoogle Scholar