A pollen diagram from Norwich Crag at Outney Common, Bungay, Suffolk

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1 Xew Phytnl. (1988), 110, ()()3 606 A pllen diagram frm Nrwich Crag at Outney Cmmn, Bungay, Sufflk BY R. G. WEST Subdepartment f Quaternary Research, University f Cambridge, Cambridge CB2.3EA, UK (Received 18 July 1988; accepted 28 July 1988) SUMMARY A pllen diagram frm Nrwich Crag at Outney Cmmn, Iungay, gives evidence f a stage with temperate frest, preceded by breal frest. A tentative crrelatin f this temperate stage with the Bramertnian Stage is suggested. Key wrds: Pllen diagrnm, breal frest, Rramertnian Stage, Nrwicli Crag. INTRODUCTION A series f fur trial brehles was made in 1964 by the East Anglian Water Cmpany at Outney Cmmn, Bungay (Fig. 1). They prved shelly sands and gravels and grey clay and silt belw terrace sands and gravels f the Waveney Valley. Nrwich Crag has lng been recrded in this area. Fr example, Wdward (1881) gave lists f mlluscs frm expsures at Ditchingham Ldge and the ft f the Bath Hills (see Fig. 1) and the brehle samples gave an pprtunity fr pllen analysis f the fine sediments assciated with the Nrwich Crag in this area. The place f the Nrwich Crag in the lcal successin, between the Upper Chalk and yunger Quaternary sands and gravels, has been described by Funnell (1955), Wilcx & Hrtn (1982) and Autn, Mrigi & Price (1985). In additin t the fur trial brehles (1 t 4, Fig. 1), the last authrs describe further brehles frm Outney Cmmn (46 and 49, Fig. 1) and there is als an earlier deep brehle (CB, Fig. 1), made in 1947 by the Water Cmpany. STRATIGRAPHY Figure 2 presents the stratigraphy f these seven brehles. The surface f Outney Cmmn is assciated with the Brme Terrace (Sparks & West, 1968; Cxn, 1979) at a height f 3-4 m abve the fjdplain f the River Waveney. This terrace is represented further dwnstream at Brme Heath and Ellingham Island (Fig. 1). The age f the Huviatile sediments underlying the surface is thught t be Wlstnian, i.e., pst-hxnian and pre- Ipsvvichian. The sands and gravels f this aggradatin ccupy the tp several metres f all the brehles. Belw them is the Nrwich Crag, represented by shelly sands and gravels and by tw substantial beds f grey silt and clay. Presumably the shelly sands and gravels are related t thse seen frmerly at arund the same lex'el at Ditchingham Ldge and the Bath Hills. The samples analysed fr pllen came frm bagged samples, each cvering 4 ft (1-3 m) depth; they were taken frm the trial brehles 1 and 2, at depths shwn in Figure 2. The resulting pllen diagram is shwn in Figure 3. It is divisible int tw pllen assemblage biznes, a and b, at 32 ft (9-8 m) belw surface, a divisin nly apprximate because f the methd f sampling. The lwer assemblage bizne, a, is characterized by a predminance f pllen f Pinus, Picea, Alnus, Betula and Ericales. In the upper assemblage bizne, b, Pinus and Ericales pllen frequencies decline and thse f Ulmus, Qtierctis and Carpinus increase, tgether with spres f Osmttnda, Tsuga pllen was recrded in bth brehles in this upper bizne. I N T R R P H K T A T I O N O F DATA The interpretatin f pllen spectra frm marine sediments is made diflicult by the pssibilities f rewrking, f ver-representatin by differential rates f transprt and f separating waterbrne frm airbrne cmpnents f the pllen influx (see West, 1961). The present inteipretatin is based n the assumptin that the pllen influx is generally representative f the reginal vegetatin. The change frm assemblage a t assemblage b indicates an expansin f mixed ak frest which fllwed a perid with a breal type f frest and higher

2 604 R, G, West NORTH SEA '; / 1 /,//OUTNEY /,f COMMON 35 "!? K i-* BUNGAY V ' S 1 /, 1 11 jj ( ~ \. y /BROOM \ HEATH i / 1 1 r / 1 ELLINGHAM ' ISLAND "- / \, / / - 30nr.., ij '- 40 ] \ ( - \\ 1 C 1 ~ ( \ _ S- \ jbeccles 90 Figure 1. Lcatin f sites in the Waveney Valley and f the Outney Cmmn brehles. CB, chalk brehle; DL, Ditchingham Ldge.

3 Nrwich Crag pllen diagram 60S d CM r > > = '1 ','l J c c..o.j. O.O. " - '.O.'O O'O.Q u Q O

4 606 R. G. West CO CT CO f\i '. J -J, J frequencies f Empetrum, Ericales and ther nntree pllen taxa. The assemblage b is very similar t the temperate spectra frm the 'Chillesfrd pllen assemblage' (West & Nrtn, 1974) in suth-east Sufflk and the assemblage at Bramertn (Funnell, Nrtn & West, 1979) near Nrwich, bth in sediments included in the Nrwich Crag Frmatin. Outney Cmmn lies in central East Anglia between these tw ther sites, s linking evidence fr a temperate stage with mixed ak frest within tbe Nrwich Crag in the Crag basins f Nrflk and Sufflk. The similarity f assemblage b with tbe Bramertn pllen diagram suggests a Bramertnian age but, in view f the multiplicity f temperate stages fund in the lwer Pleistcene in tbe Netherlands (Jng, 1988), it wuld be premature t suggest that this crrelatin was mre than tentative. The site f Outney Cmmn and the Nrwich Crag f the area clearly deserve mre detailed palentlgical and stratigraphical study, particularly since further dwn the Waveney Valley at Aldeby (Nrtn & Beck, 1972) (see Fig. 1) laminated clays with a Baventian-type pllen diagram have been recrded, s ffering the pssibility f a detailed Crag sequence in the area. ACKNOWI-FaJGEMENTS I am grateful t Mr K. B. Clarke f the East Anglian Water Cmpany fr his c-peratin and supply f brehle infrmatin at Outnty Cmmn. R Fan; R K N c R s AiTON, C. A., MRKJi, A. N. & PRICK, D. (1985). The sand and gravel resurces f the cuntry arund Harlestn and Bungay, Nrflk and Sufflk, Descriptin f 1:25000 resurce sheets cmprising parts f'rm27, 2K, 38 and 39. Keywrth, British CJeIgical Survey. COXON, P. (1979). Pleisteene eniirnmental histry in eentral East Anglia. Ph.D. thesis. University f Cambridge. FtiNNiii.z., B. M. (1955). An aecunt f the gelgy f the Bungay distriet. Transaetins f the Sufflk Naturalists' Seietv IMINNKI.I,, B. M., NOHTON, P. E. P. & WE.ST, R. G. (1979). The crag at Bramertn, near Nrwich, Nrflk. Philsphieal Transaetins f the Ryal Seiety f Lndn, B, 287, JONG, J. DI:. (1988). Climatic variability during the past three millin years, as indicated by vegetatinal e\'lutin in nrthwest F.urpe and with emphasis n data frm lhe Netherlands. Philsphieal Transaetitts f the Ryal.Seietv f Lndn, B. 318, NEiTON, P. E. P. & BECK, R. B. (1972). Lwer Pleistcene muuscan assemblages and pllen frm the crag f Aldeby (Nrflk) and Eastn Bavents (Suflblk). Bulletin f the Gelgical Seiety f Nrflk, 22, Si'AHKs, B. W. & WiisT, R. G. (1968). Interglacial depsits at Wrtwell, Nrflk. Gelgical Magazine, 105, WiiST, R. Ci. (1961). Vegetatinal histry f the Early Pleistcene f the Ryal Seiety Brehle at Ludham, Nrflk. Prceedings f the Ryal Seiety, B, 155, WRST, R. G. & NORTON, P. E. P. (1974). The Icenian Crag f suth-east Sufflk. Philsphieal Transcietins f the Ryal Seiety f Lndn, B, 269, W[i.cx, C. J. & HRTON, A. (1982). Gelgical ntes and lcal details fr 1 ; sheets TM 38 NW, NE and TM 39 SW (Bungay, Sufflk). Keywrth, Institute f Gelgical Sciences, WOODWARD, II. B. (1881), The Gelgy f the Cuntry arund Nrwieh. Memirs f the Gelgical Survey E. & W.

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