The Bramertonian Stage is the name for an early
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
biostratigraphic stage of geological history the
British Isles
The British Isles are an archipelago in the Atlantic Ocean, North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner Hebrides, Inner and Outer Hebr ...
. It precedes the
Pre-Pastonian Stage (Baventian Stage). It derives its name from
Bramerton Pits in
Norfolk
Norfolk ( ) is a Ceremonial counties of England, ceremonial county in England, located in East Anglia and officially part of the East of England region. It borders Lincolnshire and The Wash to the north-west, the North Sea to the north and eas ...
, 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).
[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.''
, jpg version 844 KB. Subcommission on Quaternary Stratigraphy, Department of Geography, University of Cambridge, Cambridge, England[ Lisiecki, L.E., 2005]
''Ages of MIS boundaries.''
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, ] The Bramertonian is correlated with the Antian stage identified from pollen assemblages in the Ludham borehole.
[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. ]
During this stage, the climate was temperate with evidence for mixed
oak
An oak is a hardwood tree or shrub in the genus ''Quercus'' of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisp ...
forest in southern England and the arrival of
hemlock. Evidence from
East Anglia
East Anglia is an area of the East of England, often defined as including the counties of Norfolk, Suffolk and Cambridgeshire, with parts of Essex sometimes also included.
The name derives from the Anglo-Saxon kingdom of the East Angles, ...
suggests sea levels were higher than they are today.
See also
*
Ice age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages, and g ...
*
Glacial period
A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate betw ...
*
Last glacial period
*
Timeline of glaciation
References
Further reading
*Bowen, D.Q., 1978, ''Quaternary geology: a stratigraphic framework for multidisciplinary work. '' Pergamon Press, Oxford, United Kingdom. 221 pp.
*Ehlers, J., P. L. Gibbard, and J. Rose, eds., 1991, ''Glacial deposits in Great Britain and Ireland.'' Balkema, Rotterdam. 580 pp
*Mangerud, J., J. Ehlers, and P. Gibbard, 2004, ''Quaternary Glaciations: Extent and Chronology 1: Part I Europe'', Elsevier, Amsterdam.
*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
*anonymous, 2007a
''Global correlation tables for the Quaternary.''Subcommission on Quaternary Stratigraphy, Department of Geography, University of Cambridge, Cambridge, England.
Glaciology
Pleistocene
Interglacials
{{Glaciology-stub