Holocene Palaeoenvironments of Broadland, England
- S.-D. Nio,
- R. T. E. Shüttenhelm and
- Tj. C. E. Van Weering
Published Online: 29 JUN 2009
Copyright © 1981 The International Association of Sedimentologists
Holocene Marine Sedimentation in the North Sea Basin
How to Cite
Coles, B. P. L. and Funnell, B. M. (2009) Holocene Palaeoenvironments of Broadland, England, in Holocene Marine Sedimentation in the North Sea Basin (eds S.-D. Nio, R. T. E. Shüttenhelm and Tj. C. E. Van Weering), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444303759.ch9
- Published Online: 29 JUN 2009
- Published Print: 23 DEC 1981
Print ISBN: 9780632008582
Online ISBN: 9781444303759
- marine transgression in Holocene epoch;
- modern distribution of camoebans and foraminiferids;
- high salt-marsh-Trochammina inflata and Jadammina macrescens;
- deposition of lower clay-known from pollen analysis;
- Holocene palaeoenvironments of Broadland
The sediment of the Broadland valleys of East Norfolk preserves evidence of two periods of marine transgression in the Holocene epoch. They are represented by estuarine lower and upper clay horizons, sandwiched between freshwater lower, middle and upper peat.
The lower clay is 12–16 m thick at the seaward limit, extends 20 km inland, and its upper surface, corresponding to a date of c.4500 BP, is at present −5·5 to −6·5 m below O.D.
The upper clay is up to 6 m thick at the coast and extends 23 km inland. Its lower surface, dated at c.2000 BP, is at −5·0 to −6·0 m O.D. at the coast, and the upper surface, dating from about 1500 BP, is at −0·05 m O.D.
Comparisons with the modern distribution of thecamoebans and foraminiferids in the River Yare and Breydon Water have allowed the definition of saline penetration and tidal levels during deposition of the estuarine clays.
A model is constructed combining progressive subsidence at 1·5 m ka−1 and cyclical sea-level changes (as inferred by Tooley, 1978), which is thought to account for the observed facies and relative sea-level changes and to have potential for projection into the future.