Global chronostratigraphic correlation of the Llandovery Series (Silurian System) in Iowa, USA, using high-resolution carbon isotope (δ13Ccarb) chemostratigraphy and brachiopod and conodont biostratigraphy

 

Authors: Waid CBT, Cramer BD

Published in: Bulletin of Geosciences, volume 92, issue 3; pages: 373 - 390; Received 1 January 2017; Accepted in revised form 8 August 2017; Online 30 September 2017

Keywords: Silurian, chronostratigraphy, U.S. Midcontinent, chemostratigraphy,

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Abstract

Chronostratigraphic correlation of Silurian units in Iowa is complicated by complex carbonate depositional environments and poor biostratigraphic control. Carbon isotope (δ13Ccarb) chemostratigraphy, when integrated with the relatively sparse conodont data, provides an extremely useful chronostratigraphic tool. Here, we integrate conodont biostratigraphic data with carbon isotope chemostratigraphic data (δ13Ccarb) for the Llandovery of Iowa. Three carbon isotope excursions were recognized within the Hopkinton and Scotch Grove formations. The late Aeronian (sedgwickii graptolite zone) and likely a heretofore unrecorded Aeronian carbon isotope excursion were recorded from the Hopkinton Formation in the SS-10 Core (Jones County). The Valgu Excursion was recorded from the uppermost Hopkinton Formation through the overlying Buck Creek Quarry Member of the Scotch Grove Formation in the Garrison Core (Benton County). The integration of conodont biostratigraphic and carbon isotope chemostratigraphic data from the Silurian of Iowa allows for the first regional chronostratigraphic correlation of these strata at a resolution finer than stage level. The oxygen and carbon isotope values from the Garrison Core and the evidence for post-diagenetic karstification and fluid movement may provide further evidence that the dolomitization process of the LaPorte City Formation was halted by the influx of meteoric phreatic water.

References

BANNER, J. & HANSON, G. 1990. Calculation of simultaneous isotopic and trace element variations during water-rock interaction with applications to carbonate diagenesis. Geochimica et Cosmochimica Acta 54, 3123-3137.View article

BERGSTRÖM, S., KLEFFNER, M. & SCHMITZ, B. 2012. Late Ordovician-Early Silurian δ13C chemostratigraphy in the Upper Mississippi Valley: implications for chronostratigraphy and depositional interpretations. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 102, 159-178.View article

BOUCOT, A. & EHLERS, G. 1963. Two new genera of Stricklandid brachiopods. Contributions from the Museum of Paleontology, The University of Michigan 18, 47-66.

BRANSON, E. & MEHL, M. 1933. Conodont Studies. Missouri University Studies 8, 349 pp.

CRAMER, B.D., BRETT, C.E., MELCHIN, M.J., MÄNNIK, P., KLEFFNER, M.A., MCLAUGHLIN, P.I., LOYDELL, D.K., MUNNECKE, A., JEPPSSON, L., CORRADINI, C., BRUNTON, F.R. & SALTZMAN, M.R. 2011. Revised correlation of Silurian Provincial Series of North America with global and regional chronostratigraphic units and δ13Ccarb chemostratigraphy. Lethaia 44, 185-202.View article

DAVIES, J., WATERS, R., MOLYNEUX, S., WILLIAMS, M., ZALASIEWICZ, J., VANDENBROUCKE, T. & VERNIERS, J. 2013. A revised sedimentary and biostratigraphical architecture for the Type Llandovery area, Central Wales. Geological Magazine 150, 300-332.View article

DAVIES, J., WATERS, R., MOLYNEUX, S., WILLIAMS, M., ZALASIEWICZ, J. & VANDENBROUCKE, T. 2016. Gauging the impact of glacioeustasy on a mid-latitude early Silurian margin, mid Wales, UK. Earth-Science Reviews 156, 82-107.View article

ETHINGTON, R. 1959. Conodonts of the Ordovician Galena Formation. Journal of Paleontology 33, 257-292.

GLENNISTER, A. 1957. The conodonts of the Ordovician Maquoketa Formation in Iowa. Journal of Paleontology 33, 715-736.

JEPPSSON, L. 1997. A new latest Telychian, Sheinwoodian and early Early Homerian (Early Silurian) Standard Conodont Zonation. Transactions of the Royal Society of Edinburgh: Earth Sciences 88, 91-114.View article

JEPPSSON, L. & ANEHUS, R. 1995. A buffered formic acid technique for conodont extraction. Journal of Paleontology 69, 790-794.View article

JOHNSON, M. 1977. Succession and replacement in the development of Silurian brachiopod populations. Lethaia 10, 83-93.View article

JOHNSON, M. 1983. New member names for the lower Silurian Hopkinton Dolomite of eastern Iowa. Proceedings of the Iowa Academy of Science 90, 13-18.

JOHNSON, M. 1987. Extent and bathymetry of North American platform seas in the early Silurian. Paleoceanography 2, 185-211.View article

JONES, O.T. 1925. The Geology of the Llandovery district: part I. The Southern Area. Quarterly Journal of the Geological Society, 81, 344-388.View article

KALJO, D. & MARTMA, T. 2006. Application of carbon isotope stratigraphy to dating the Baltic Silurian rocks. GFF 128, 123-129.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, 297-312. In LANDING, E. & JOHNSON, M. (eds) Silurian Cycles: Linking Dynamic Stratigraphy with Atmospheric, Oceanic, and Tectonic Changes. New York State Museum Bulletin 491.

KALJO, D., MARTMA, T., GRYTSENKO, V., BRAZAUSKAS, A. & KAMINSKAS, D. 2012. Přídolí carbon isotope trend and upper Silurian to lowermost Devonian chemostratigraphy based on sections in Podolia (Ukraine) and the East Baltic area. Estonian Journal of Earth Sciences 61, 162-180.View article

KALJO, D., MARTMA, T., MÄNNIK, P. & VIIRA, V. 2003. Implications of Gondwana glaciations in the Baltic Late Ordovician and Silurian and a carbon isotopic test of environmental cyclicity. Bulletin de la Societe Geologique de France 174, 59-66.View article

LUDVIGSON, G.A., WITZKE, B.J. & GONZÁLEZ, L. 1992. Observations on the diagenesis and stable isotopic compositions of Silurian carbonates in Iowa. Field trip guidebook to Silurian exposures in Jones and Linn Counties. Iowa Geological Survey Guidebook Series 11, 73-83.

MACKE, D. 1995. Illinois Basin Province (064). In GAUTIER, D., DOLTON, G., TAKAHASHI, K. & VARNES, K. (eds) National assessment of United States oil and gas resources - Results, methodology, and supporting data: United States Geological Survey Digital Data Series DDS-30, Release 2, accessed 4/20/15 at http://certmapper.cr.usgs.gov

MÄNNIK, P. 1998. Evolution and taxonomy of the Silurian conodont Pterospathodus. Paleontology 41, 1001-1050.

MÄNNIK, P. 2007a. An updated Telychian (Late Llandovery, Silurian) conodont zonation based on Baltic faunas. Lethaia 40, 45-60.View article

MÄNNIK, P. 2007b. Recent developments in the Upper Ordovician and lower Silurian conodont biostratigraphy in Estonia. Estonian Journal of Earth Sciences 56, 35-46.

MCADAMS, N.E.B., BANCROFT, A.M., CRAMER, B.D. & WITZKE, B.J. 2017. Integrated carbon isotope and conodont biochemostratigraphy of the Silurian (Aeronian-Telychian) of the East-Central Iowa Basin, Iowa, USA. Newsletters on Stratigraphy 50, 391-416.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., MACRAE, K.D. & BULLOCK, P. 2015.A multi-peak organic carbon isotope excursion in the late Aeronian (Llandovery, Silurian): evidence from Arisaig, Nova Scotia, Canada. Palaeoworld 24, 191-197.View article

MELCHIN, M.J., SADLER, P.M. & CRAMER, B.D. 2012. Chapter 21: The Silurian Period, 525-588. In GRADSTEIN, F., OGG, J., SCHMITZ, M. & OGG, G.(eds) The Geologic Time Scale 2012. Elsevier, New York.

METZGER, R. 2005. Conodont biostratigraphy of the Scotch Grove and LaPorte City formations (late Llandovery-early Wenlock; Silurian) in eastern Iowa. Bulletins of American Paleontology 369, 93-104.

MUNNECKE, A., CALNER, M., HARPER, D.A.T. & SERVAIS, T. 2010. Ordovician and Silurian sea-water chemistry, sea level, and climate: A synopsis. Palaeogeography, Palaeoclimatology, Palaeoecology 296, 389-413.View article

SALTZMAN, M.R. 2002. Carbon isotope (δ13C) stratigraphy across the Silurian-Devonian transition in North America: evidence for a perturbation of the global carbon cycle. Palaeogeography, Palaeoclimatology, Palaeoecology 187, 83-100.View article

SALTZMAN, M.R. & THOMAS, E. 2012. Chapter 11: Carbon Isotope Stratigraphy, 201-232. In GRADSTEIN, F., OGG, J., SCHMITZ, M. & OGG, G.(eds) The Geologic Time Scale 2012. Elsevier, New York.

ŠTORCH, P. & FRÝDA, J. 2012. The late Aeronian graptolite sedgwickii Event, associated positive carbon isotope excursion and facies changes in the Prague Synform (Barrandian area, Bohemia). Geological Magazine 149, 1089-1106.View article

TORSVIK, T., SMETHURST, M., MEERT, J., VAN DER VOO, R., MCKERROW, W., BRASIER, M., STURT, B. & WALDERHAUG, H. 1996. Continental break-up and collision in the Neoproterozoic and Palaeozoic - A tale of Baltica and Laurentia. Earth-Science Reviews 40, 229-258.View article

WAID, C.B. & CRAMER, B.D. 2017. Telychian (Llandovery, Silurian) conodonts from the LaPorte City Formation of eastern Iowa (East-Central Iowa Basin) and their implications for global Telychian conodont biostratigraphic correlation. Palaeontologia Electronica 20, 1-37.

WALLISER, O. 1964. Conodonten des Silurs. Abhandlungen des Hessischen Landesamtes für Bodenforschung 41,1-106.

WITZKE, B. 1981. Stratigraphy, depositional environments, and diagenesis of the eastern Iowa Silurian sequence. 574 pp. Ph.D. thesis, The University of Iowa, Iowa City, USA.

WITZKE, B. 1992. Silurian stratigraphy and carbonate mound facies of Eastern Iowa. Field trip guidebook to Silurian exposures in Jones and Linn Counties, Iowa Geological Survey Guidebook Series 11, 3-63.