Runton, Norfolk, England)
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Cranium, jrg. 9, no. 2, pag. 77-84, augustus 1992 The Pleistocene Vertebrate Faunas of West Runton, Norfolk, England A.J. Stuart Summary the Norfolk is the fossil vertebrate the Cromer Forest Bed For- West Runton, on coast, most important single locality of marine fauna mation. The Lower Pleistocene (Pre-Pastonian and Pastonian stages) ’crags’ have yielded a sparse inclu- ding Mammuthus meridionalis, Mimomys pliocaenicus, and M. blanci. The fluvial of the West Runton Cromerian have organic deposits Freshwater Bed, type site, produced an exceptionally rich early MiddlePleistocene vertebrate assemblage, comprising: 8 fish taxa; 5 amphibians; 3 reptiles; several birds; and 43 mammals. The mammals include: voles Mimomys savini and and Pliomys episcopalis; extinct beaver Trogontherium cuvieri; monkey Macaca sylvanus, mammoth Mammuthus cf. meridionalis, rhinoceros Dicerorhinus etruscus, and giant deer Megaloceros verticornis. Pollen and macrofossils show that this fauna lived in association with forest in the first half of plant regional temperate the temperate stage. Samenvatting West Runton, aan de Norfolk kust in Engeland, is de meest belangrijke vindplaats van vertebratenfossielen afkomstig uit de Cromer Forest Bed Formatie. In de Vroeg Pleistocene (Pre-Pastonien en Pastonien stages) mariene ’crags’ zijn een klein aantal M. relatief zoogdierresten van o.a. Mammuthus meridionalis, Mimomys pliocaenicus en blanci verzameld. de Freshwater hebben De organische, fluviatiele afzettingen van West Runton Bed, type-lokaliteit van het Cromerien, Midden vertebratenfauna 8 5 een buitengewoon rijke vroeg Pleistocene opgeleverd met soorten vissen, soorten amphi- biën, 3 soorten reptielen, meerdere vogels en 43 soorten zoogdieren. De zoogdierfauna bevat o.a. woelmuizen Mimomys en de bever de de mammoet savini Pliomys episcopalis, uitgestorven Trogontherium cuvieri, aap Macaca sylvanus, Mam- cf. meridionalis, neushoornDicerorhinus muthus de etruscus en het reuzenhertMegaloceros verticornis. Pollen dat de in de helft en plantaardige macroresten tonen aan faunaheeft geleefd een bosrijke omgeving tijdens eerste van de gematigd warme periode. Introductie and Pastonian of Lower Pleistocene age, and the Bees- tonian and Cromerian dating from the early Middle The Cromer Forest Bed Formation (C.F.B.F.), exposed Pleistocene. Some deposits assigned to the Beestonian along the coasts of northeast Norfolk and Suffolk, has date from distinct Lower Pleistocene cold may a stage. been famous for its fossil mammal remains since the Bed also Recent work suggests that the Forest covers early part of the last century (GREEN, 1842; OWEN, one or more early MiddlePleistocene temperate stages 1846). The classic nineteenth century study of the stra- which are post- Cromerian, but still pre-Anglian tigraphy and palaeobotany of these complex deposits by (MEIJER & PREECE, 1992; STUART, 1992). Clement Reid (REID, 1882; 1890), was matched by ex- work the vertebrates cellent on by E.T. NEWTON (e.g. The Forest Bed mammal "localities" are shown in Fig. 1. beach 1882a; 1886; 1891). Forest Bed fossils found on the at Eccles, appear contributions Other major on the vertebrates include to have been washed out of deposits below low tide le- last those made century by OWEN (e.g. 1846) and vel. Stray, probably wave-transported, finds occur on and earlier this the southeast DAWK1NS (e.g. 1883); century by HIN- the beaches even further to at Sea Palling and should be stressed TON (1908; 1911; 1926), AZZAROLI (1953). More and Winterton. It that many of the includes Bed recent work MCWILLIAMS (1967); STUART Forest 'localities', as recorded in museum labels fossil (1975; 1982; 1992); STUART & WEST (1976); and LISTER and catalogues, are not specific sites, but merely indication of where (1992a; 1992b). give a general specimens were in relation the coastal found to nearest village or town. WEST'S (1980) massive reinterpretation of the stratigra- in fossils found the Moreover, many cases were loose on phy and of the C.F.B.F., utilizing palyno- palaeobotany been washed of beach, having out deposits in the cliffor - - a technique unknown to Reid provided an inva- logy it is difficult foreshore, so that or impossible to assign luable framework for sorting out the sequence of these units. to particular stratigraphic Exposures were vertebrate faunas. According to West the C.F.B.F. co- better in the generally past, as nowadays most are obs- the vers several climate-based stages, from oldest to the cured by sea defences, but some localities are still avai- Pastonian youngest: Pre-Pastonian (cold); (temperate); lableand important finds continue to be made. Beestonian (cold); and Cromerian (temperate), the de- posits of which are succeeded by tills and outwash of The most important single locality where Forest Bed hiatus the Anglian Glaciation. A major stratigraphical is vertebrateshave been found in situ is the cliff section at within the with the Pre-Pastonian the present sequence, West Runton (Figs. 2,3), stratotype for the Cromeri- 77 in situ. Fig. 1: Forest Bed Vertebrate Localities. Open circles indicate localities where Forest Bed deposits do not occur Corton, Pakefield and Kessingland are in the County of Suffolk; the rest are in Norfolk. 1: Forest Bed. de Forest bed niet in situ voorkomen. Fig. Vindplaatsen van gewervelden van Open rondjes geven plaatsen aan waar afzettingen Corton, Pakefield en Kessingland liggen in Suffolk, de andere in Norfolk. Pre-Pastonian and Pastonian few an Temperate Stage, and designated a geological stages (WEST,1980). A S.S.S.I. (Site of Special Scientific Interest) by English large-mammal remains have been found in the fore- Natural EnvironmentResearch a molar of the Nature (formerly Coun- shore exposures, including extinct ele- cil). Although threatened on more than one occasion, phant Mammuthus meridionalis from the Stone Bed this Vole material prime palaeontological locality is still allowed to (Pre-Pastonian a substage) (WEST, 1980). erode less and thus remains from more or naturally, available was obtained by sieving crag dug beneath the for study. beach by mechanical excavator during the construction wall of a concrete sea immediately to the east of West Two of and faunas in groups deposits widely separated Runton Gap (MAYHEW & STUART, 1986). this The Lower Pleis- time are present at locality. older, which tocene, assemblages need more detailed study and are The vole fauna, comprises Mimomys pliocaeni- considered only briefly here. cus, Mimomys reidi, Mimomys newtoni, Mimomys blanci and Mimomys pitymyoides, is very different to that of Cold and Pastonian Crag (pre-Pastonian Stage Tempe- Freshwater the West Runton Bed, which occurs in a rate Stage) stratigraphically higher position, but is similar to those East Runton recorded from (MAYHEW & STUART, Overlying the Upper Chalk, which can be seen exposed A 1986). desman upperP4 from the same deposits has on the foreshore at low tide, are Lower Pleistocene ma- been referred to al. rine Galemys kormosi by HARRISON et deposits; the Stone Bed and crag ("Weybourne The above material is in the Universi- which (1988). preserved Crag") occur both on the foreshore and beneath ty Museumof Zoology, Cambridge. the modern beach. Pollen assemblages obtained from silt horizons show the interdigitated that the crag covers 78 Fig. 2: Schematic section of cliff and foreshore deposits at West Runton, Norfolk (based on WEST, 1980). Length of section approximately 500 metres; depth 22 metres. The V-shaped structure is an ice-wedge cast. Sediment Environment Stage 8. tilland outwash sands and gravels, glacial Anglan Cold Stage occasional ice wedge casts penetrate the underlying sands and silts permafrost Anglian Cold stage 7. laminated silts and sands (below), marine Cromerian Temperate Stage, sands (above) tidal substage III, IV 6. gravel ("Monkey Gravel") marine Cromerian TemperateStage, substage III palaeoasol subaerial 5. West Runton Freshwater Bed freshwater,fluvial Cromerian TemperateStage, substage Ib-IIb 4. Calcareous silt freshwater,lacustrine Late Beestonian Cold Stage to early Cromerian substage la 3. Gravels and sands marine Beestonian Cold Stage 2. Crag and silts marine Pre-Pastonian Cold Stage and Pastonian Temperate Stage 1. Stone Bed on frost-shattered chalk marine Pre-Pastonian Cold Stage The Pleistocene deposits rest on Chalk (Upper Cretaceous, Campanian). 2: Schematisch de klif de de kust West Norfolk de door- Fig. profiel van en afzettingen voor van Runton, (gebaseerd op WEST, 1980). Lengte van 500 snede is ongeveer m.; diepte 22 m. De V-vormige struktuur is een vorstwig. West Ronton Freshwater Bed beds fluvial muds and (Cromerian Temperate c-e, shelly organic sands with nu- small Stage) merous reworked marl lumps and pebbles (mainly subzones - flint), with pollen spectra essentially of Cr lb This famous deposit, known since the early nineteenth Cr Ila. The clast size decreases upwards and the upper has of the richest century, produced one Quaternary of the bed muds part deposit, f, comprises detritus vertebrate faunas in Europe. So far it has escaped being (shelly in part), mainly of subzone Cr lib age. The alte- obscured coastal defences and by sea important new red top of the bed, interpreted as a palaeosol, indicates including new species continues to be material, records, substantial of mari- a period subaerial exposure prior to found. basal ne deposition of the overlying gravel ("Monkey Freshwater The West Runton Bed occupying a broad Gravel") and thin bedded silts and sands attributed to channel about