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A chronological framework for the British Quaternary based on Bithynia opercula

Publikation: Bidrag til tidsskriftLetterForskningfagfællebedømt

  • Kirsty E. H. Penkman
  • Richard C. Preece
  • David R. Bridgland
  • David H. Keen
  • Tom Meijer
  • Simon A. Parfitt
  • Tom S. White
  • Collins, Matthew James

Marine and ice-core records show that the Earth has experienced a succession of glacials and interglacials during the Quaternary (last ∼2.6 million years), although it is often difficult to correlate fragmentary terrestrial records with specific cycles. Aminostratigraphy is a method potentially able to link terrestrial sequences to the marine isotope stages (MIS) of the deep-sea record. We have used new methods of extraction and analysis of amino acids, preserved within the calcitic opercula of the freshwater gastropod Bithynia, to provide the most comprehensive data set for the British Pleistocene based on a single dating technique. A total of 470 opercula from 74 sites spanning the entire Quaternary are ranked in order of relative age based on the extent of protein degradation, using aspartic acid/asparagine (Asx), glutamic acid/glutamine (Glx), serine (Ser), alanine (Ala) and valine (Val). This new aminostratigraphy is consistent with the stratigraphical relationships of stratotypes, sites with independent geochronology, biostratigraphy and terrace stratigraphy. The method corroborates the existence of four interglacial stages between the Anglian (MIS 12) and the Holocene in the terrestrial succession. It establishes human occupation of Britain in most interglacial stages after MIS 15, but supports the notion of human absence during the Last Interglacial (MIS 5e). Suspicions that the treeless 'optimum of the Upton Warren interstadial-at Isleworth pre-dates MIS 3 are confirmed. This new aminostratigraphy provides a robust framework against which climatic, biostratigraphical and archaeological models can be tested.

OriginalsprogEngelsk
TidsskriftNature
Vol/bind476
Udgave nummer7361
Sider (fra-til)446-449
Antal sider4
ISSN0028-0836
DOI
StatusUdgivet - 2011
Eksternt udgivetJa

ID: 229377935