The Bramertonian Stage is the name for an early
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...
biostratigraphic stage in the
British Isles
The British Isles are a group of islands in the 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 and Outer Hebrides, the Northern Isl ...
. It precedes the
Pre-Pastonian Stage The Pre-Pastonian Stage or Baventian Stage (from Easton Bavents in Suffolk), is the name for an early Pleistocene stage used in the British Isles. It precedes the Pastonian Stage and follows the Bramertonian Stage. This stage ended 1.806 Ma (millio ...
(Baventian Stage). It derives its name from
Bramerton Pits
Bramerton Pits is a geological Site of Special Scientific Interest north of the village of Bramerton in Norfolk on the southern banks of the River Yare. It is a Geological Conservation Review site.
The site is composed of two disused gravel pit ...
in
Norfolk
Norfolk () is a ceremonial and non-metropolitan county in East Anglia in England. It borders Lincolnshire to the north-west, Cambridgeshire to the west and south-west, and Suffolk to the south. Its northern and eastern boundaries are the Nor ...
, 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 forest in southern England and the arrival of
hemlock. Evidence from
East Anglia
East Anglia is an area in the East of England, often defined as including the counties of Norfolk, Suffolk and Cambridgeshire. The name derives from the Anglo-Saxon kingdom of the East Angles, a people whose name originated in Anglia, in ...
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 gre ...
*
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 betwe ...
*
Last glacial period
*
Timeline of glaciation
There have been five or six major ice ages in the history of Earth over the past 3 billion years.
The Late Cenozoic Ice Age began 34 million years ago, its latest phase being the Quaternary glaciation, in progress since 2.58 million years ago ...
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