Retreat of the Late Pliocene and Lower Pleistocene Crag sea
Table 2. Stratigraphy of the Nonvich Crag, Wroxham Crag &Cromer Forest-bed Formations
Formation/Member Former terms Stage
Cromer Forest-bed Wroxham Crag
Formation Formation
(Biostratigraphy) (Lithostratigraphy)
Barton Member (Arctic Bed) Cromerian IV
Mundesley Member Mundesley Member (Leda myalis Bed) Cromerian III, IV
W. Runton Member { (U. Freshwater Bed) Cromerian I, II
Runton Member {How Hill Member Beestonian*
{ (Forest Bed)**
Paston Member { Pastonian
{ (L. Freshwater Bed)**
Sheringham Member { Pre-Pastonian
Sidestrand Member Dobbs Member (Weybourne Crag) Pre-Pastonian
Norwich Crag Formation
Westleton Member
Chillesford/
Easton Bavents Members
College Farm Member
Chillesford Church/
Creeting Members
(Westleton Beds)
(Chillesford/
Baventian Clay)
(College Farm Silty Clay)
(Chillesford Crag/
Creeting Sand)
Baventian
Baventian
?Bramertonian/
Antian
Bramertonian/
Antian
Red Crag Formation
* Beestonian may cover 1.2 million years and up to 20 cold-warm cycles, yet to be defined.
** Lower Freshwater Bed and Forest Bed were terms applied to beds which have been found
subsequently to be of different ages at different sites. The attributions here are merely indicative.
*** Sidestrand Member formerly regarded as uppermost member of the Norwich Crag (West,
1980), now regarded as lowermost member of the Wroxham Formation (Rose et al., 2000, 2001)
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Essex Naturalist (New Series) 18 (2001)