The Bramertonian Stage is the name for an early Pleistocene biostratigraphic stage of geological history the British Isles. It precedes the Pre-Pastonian Stage (Baventian Stage). It derives its name from Bramerton Pits in Norfolk, where the deposits can be found on the surface. The exact timing of the beginning and end of the Bramertonian Stage is currently unknown. It is only known that it is equivalent to the Tiglian C1-4b Stage of Europe and early Pre-Illinoian Stage of North America. It lies somewhere in time between Marine Oxygen Isotope stages 65 to 95 and somewhere between 1.816 and 2.427 Ma (million years ago).[1][2][3][4] The Bramertonian is correlated with the Antian stage identified from pollen assemblages in the Ludham borehole.[5][6]
During this stage, the climate was temperate with evidence for mixed oak forest in southern England and the arrival of hemlock. Evidence from East Anglia suggests sea levels were higher than they are today.
See also
editReferences
edit- ^ McMillan, A.A., 2005, A provisional Quaternary and Neogene lithostratigraphic framework Great Britain. Netherland Journal of Geosciences. vol. 84, no. 2, pp, 87–107.
- ^ Gibbard, P.L., S. Boreham, K.M. Cohen and A. Moscariello, 2007, Global chronostratigraphical correlation table for the last 2.7 million years v. 2007b. Archived 2008-09-10 at the Wayback Machine, jpg version 844 KB. Subcommission on Quaternary Stratigraphy, Department of Geography, University of Cambridge, Cambridge, England
- ^ Lisiecki, L.E., 2005, Ages of MIS boundaries. LR04 Benthic Stack Boston University, Boston, MA
- ^ Lisiecki, L.E., and M.E. Raymo, 2005, A Pliocene-Pleistocene stack of 57 globally distributed benthic d18O records. Paleoceanography. vol. 20, PA1003, doi:10.1029/2004PA001071
- ^ West, RG (1962). Vegetational history of the Early Pleistocene of the Royal Society Borehole at Ludham, Norfolk. Proceedings of the Royal Society of London, B155, pp.437-453
- ^ Gibbard, PL, Zalasiewicz, JA & Mathers, SJ (1998). Stratigraphy of the marine Plio-Pleistocene crag deposits of East Anglia. In: van Kolfschoten, T & Gibbard, PL (eds). The Dawn of the Quaternary - proceedings of the SEQS-EuroMam Symposium : Kerkrade, 16-21 June 1996. Netherlands Institute of Applied Geoscience, 1998. ISBN 9072869613
Further reading
edit- Bowen, D.Q., 1978, Quaternary geology: a stratigraphic framework for multidisciplinary work. Pergamon Press, Oxford, United Kingdom. 221 pp. ISBN 978-0-08-020409-3
- Ehlers, J., P. L. Gibbard, and J. Rose, eds., 1991, Glacial deposits in Great Britain and Ireland. Balkema, Rotterdam. 580 pp ISBN 978-90-6191-875-2
- Mangerud, J., J. Ehlers, and P. Gibbard, 2004, Quaternary Glaciations: Extent and Chronology 1: Part I Europe, Elsevier, Amsterdam. ISBN 0-444-51462-7
- Sibrava, V., Bowen, D.Q, and Richmond, G.M., 1986, Quaternary Glaciations in the Northern Hemisphere, Quaternary Science Reviews, vol. 5, pp. 1–514.
External links
edit- anonymous, 2007a, Global correlation tables for the Quaternary. Subcommission on Quaternary Stratigraphy, Department of Geography, University of Cambridge, Cambridge, England.