The surtace and subsurtace Holocene deposits ot the macrotidal barrier coast ot north Norfolk. between Hunstanton and Wevbourne. have been investisated bv a coordinated studv ot sedimentarv and foraminiteral parameters. 14 distinct sedimentarv and vesetational areas (environmental units) are recognisable from aerial photographs, trom which a map of their spatial distributions has been produced. Barriers are both prograding (Holkham Gap) and eroding (Brancaster to Thornham) due to variations in sediment supply and land reclamation. Present models of sediment movement underestimate the offshore supply to the coast. In particular the input of sediment to the Holkham Gap area from a easterly offshore movement. Removal of fine sand to the offshore zone occurs at channel inlets although westerly spit development of Blakeney Point has created an embayment at Stiffkey where finer sands accumulate. Barrier formation observed at Holkham Gap indicates the emplacement and stabilisation of beach bars to be a major formational process. Sedimentarv parameter ranges delineate silt based units but show considerable overlap between sand-based units. Foraminiferal species assemblages delineate 4 significant cluster groupings also separating silt based units but amalgamating sand based units into one cluster group. The environmental unit determination of subsurface samples was supplemented bv stratigraphic relationship interpretations for sand based units. 9 subsur~ace environmental units have been separated. (i) back barrier sand and dune. (ii) peat. (iii) inter-tidal gravel, (iv) inter-tidal sand, (v) channel sand, (vi) inter-tidal silty sand, (vii) inter-tidal mud and marsh creek, (viii) lower marsh and (ix) upper marsh.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:378907 |
Date | January 1986 |
Creators | Pearson, I. |
Publisher | University of East Anglia |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
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