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Updated: May 2, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
22.7K
A chronological framework for the British Quaternary based on Bithynia opercula.
Kirsty E H Penkman1, Richard C Preece, David R Bridgland
1BioArCh, Department of Archaeology, University of York, York YO10 5DD, UK. kirsty.penkman@york.ac.uk
Nature
|August 2, 2011
Summary
Aminostratigraphy using gastropod opercula provides a robust timeline for British Quaternary sequences. This method links terrestrial records to marine isotope stages, revealing human occupation patterns throughout glacial and interglacial cycles.
Area of Science:
- Paleoclimatology
- Quaternary Geology
- Biostratigraphy
Background:
- Earth's Quaternary period features cyclical glacials and interglacials, challenging correlation of terrestrial records.
- Aminostratigraphy offers a potential method to align terrestrial sequences with marine isotope stages (MIS).
Purpose of the Study:
- To develop a comprehensive aminostratigraphy for the British Pleistocene using freshwater gastropod opercula.
- To establish a robust dating framework for Quaternary terrestrial sequences.
Main Methods:
- Analysis of amino acid degradation (Asx, Glx, Ser, Ala, Val) in 470 opercula from 74 British sites.
- Relative age ranking based on protein degradation extent.
Main Results:
- A new aminostratigraphy consistent with existing stratigraphical data was established.
- Four interglacial stages between Anglian (MIS 12) and Holocene confirmed.
- Human occupation in Britain identified in interglacial stages post-MIS 15, with absence during MIS 5e.
- Confirmation that the Upton Warren interstadial optimum predates MIS 3.
Conclusions:
- The new aminostratigraphy provides a reliable framework for Quaternary research.
- Supports detailed reconstruction of past climate, biostratigraphy, and archaeological events.
- Refines understanding of human presence and absence during key Quaternary periods.
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