Cromer Forest-bed Formation Research Articles

Early Middle Pleistocene sediments at Sidestrand, northeast Norfolk, yield the most extensive preglacial cold stage beetle assemblage from Britain

Fluvial sediments (Cromer Forest-bed Formation) at Sidestrand, northeast Norfolk, have yielded the most extensive preglacial early Middle Pleistocene cold (arctic) stage beetle assemblage known from Britain. The assemblage is composed of 59 taxa indicating severely cold and continental climatic conditions. Mutual Climatic Range reconstructions suggest that the mean temperature of the warmest month (July) was between 10 °C and 13 °C and the mean temperature of the coldest months (January and February) between −17 °C and −10 °C, although the actual palaeotemperatures were probably towards the lower end of these ranges. Associated pollen and macroflora remains were poorly represented but all are known from other cold stage contexts.Excavations reveal that this freshwater arctic assemblage occurs within units between two important stratigraphic marker horizons, the Sidestrand Hall Member of the Cromer Forest-bed Formation and the first lowland glacigenic deposit (Happisburgh Till Member) in eastern England, although the ages of both remain equivocal. Recent amino-acid chronologies of molluscan faunas from the Sidestrand Hall Member indicate a MIS 13 age, with by inference a MIS 12 age for the overlying arctic units with cold beetle fauna and for the Happisburgh Till Member. However, the arctic units are separated from the two stratigraphic marker horizons by shallow marine deposits (Wroxham Crag Formation) demonstrating at least two intervening phases of marine transgression and a cold climate marine regression. The climatic significance of these marine transgressions and their chronostratigraphic implications are currently uncertain.

A butchered bone from Norfolk: evidence for very early human presence in Britain

Before the Anglian glaciation some 450,000 years ago, much of England was drained by large rivers that deposited sediments - known as the Cromer Forest-bed Formation - now exposed along the coast of East Anglia. The Forest-bed has yielded a great variety of fossils but until now no definite evidence of human activity. The recent discovery of cut marks on a bison bone collected from it in the nineteenth century demonstrates conclusively that humans were present in this part of East Anglia over half a million years ago.

The first British record of Actinidia faveolata C.Reid and E.M.Reid (Actinidiaceae family)

Archaeological artefact-bearing Pleistocene fluvial sediments, which form part of the Cromer Forest-bed Formation, below the modern beach just south-east of Happisburgh, Norfolk, UK (Happisburgh Site 1), yielded a diverse plant macrofossil assemblage that included a seed fragment of Actinidia faveolata C.Reid and E.M.Reid – an extinct relative of the modern Kiwi fruit (Actinidia deliciosa (A.Chev.) C.F.Liang and A.R.Ferguson, Actinidiaceae family). This is the first record of this taxon in the British Isles. Previously, this extinct species has been found in Upper Oligocene sediments from West Siberia and from Miocene, Pliocene and Early Pleistocene sediments in Europe. The stratigraphical and palaeoenvironmental setting of this find is briefly considered followed by a detailed description of the fossil with a comparison of specimens from the type area. The archaeological and biostratigraphical implications of this record are also discussed.

The status of the Hill House ‘Formation’ at Happisburgh, Norfolk, England

Sediments at a site at Happisburgh, Norfolk, from which an important assemblage of flint artefacts had been excavated, were recently described. This locality, termed Happisburgh 3 (NGR TG380313; 52°49_36″N, 1°31_58″E), occurs on the NE coast of Norfolk. These sediments consist of a complex of freshwater, estuarine and inter-tidal deposits, which were deposited during the Early and early Middle Pleistocene. These deposits were defined as an independent lithostratigraphical unit, the Hill House Formation. However, as the deposits already formed part of the Cromer Forest-bed Formation, they cannot themselves have the same status. It is therefore proposed that the unit be referred to as the Hill House Member of the Cromer Forest-bed Formation.

The first record of “spelaeoid” bears in Arctic Siberia

For a long time, “spelaeoid” (cave-bear-like) bears, Ursus ( Spelearctos) spp., were believed to be almost purely European animals. Their geographic range has recently been extended to the east, in southern Siberia, Transbaikalia, Kirghizia, Mongolia and Korea. Two unexpected new findings, presented here in detail, significantly change existing views on the distribution of cave bears; both were found in North-Eastern Siberia, far beyond the Arctic Circle, more than 1500 km to the north-east of the previously accepted range. One of the fossils is a mandible, found near the town of Cherskiy at 68.73°N, 161.38°E. The analysis of local geology and accompanying mammal fossils suggests that it comes from the Olyorian Fauna (Early to early Middle Pleistocene). Morphologically, the Cherskiy mandible is closest to Ursus savini, a small middle Pleistocene cave bear from the British Cromer Forest-bed Formation, but differs in having a slightly more advanced dentition, and thus it is described as a new subspecies Ursus savini nordostensis. Another newly recognized fossil of the “spelaeoid” bear is an astragalus found at the Oskhordokh site at 67.54°N, 135.67°E, on a large gravel bar on the right bank of the Adycha River. This specimen is attributed to Ursus cf . deningeri. The paper also presents an interesting example of the interaction between classical and “molecular” palaeontology. The new finds significantly change existing ideas on the ecology and evolution of cave bears, some of the most remarkable members of the extinct Pleistocene megafauna.

Middle Pleistocene biota of the early Anglian ‘Arctic Fresh-water Bed’ at Ostend, Norfolk, UK

At three sites along the North Norfolk coast, freshwater sediments containing arctic plants have been reported to occur immediately beneath the glacial deposits. The sections at Mundesley and Beeston are no longer visible but a small exposure of this ‘Arctic Fresh-water Bed’ has recently been rediscovered at Ostend near Bacton. The fossils from this deposit are distinctly high boreal/arctic in character, indicating a small, possibly ephemeral, pool in a generally open landscape supporting some dwarf shrubs and conifers. Noteworthy records include three beetle species (Pterostichus brevicornis, P. middendorffi and Helophorus obscurellus) that today have their closest occurrences on either the Kanin or Kola peninsulas in arctic Russia. A Mutual Climatic Range reconstruction on the limited beetle fauna suggests that the mean temperatures of the warmest and coldest months were between 9°C and 11°C and between −36°C and −10°C, respectively. Other noteworthy occurrences include the aquatic pulmonate gastropod Gyraulus rossmaessleri (second and earliest British record), the ostracod Amplocypris tonnensis (earliest British record), ground squirrel (Spermophilus sp.) and the first record of arctic lemming (Dicrostonyx sp.) from the Cromer Forest-bed Formation (CF-bF). The ‘Arctic Fresh-water Bed’ has been assigned to the Bacton Member of the CF-bF and formed during the early Anglian, correlated with Marine Isotope Stage (MIS) 12 of the deep sea record. The Ostend assemblage is therefore important in providing a glimpse of conditions that occurred during a major cold stage in the early Middle Pleistocene.

Biostratigraphic and aminostratigraphic constraints on the age of the Middle Pleistocene glacial succession in north Norfolk, UK

AbstractConsiderable debate surrounds the age of the Middle Pleistocene glacial succession in East Anglia following some recent stratigraphical reinterpretations. Resolution of the stratigraphy here is important since it not only concerns the glacial history of the region but also has a bearing on our understanding of the earliest human occupation of north‐western Europe. The orthodox consensus that all the tills were emplaced during the Anglian (Marine Isotope Stage (MIS) 12) has recently been challenged by a view assigning each major till to a different glacial stage, before, during and after MIS 12. Between Trimingham and Sidestrand on the north Norfolk coast, datable organic sediments occur immediately below and above the glacial succession. The oldest glacial deposit (Happisburgh Till) directly overlies the ‘Sidestrand Unio‐bed’, here defined as the Sidestrand Hall Member of the Cromer Forest‐bed Formation. Dating of these sediments therefore has a bearing on the maximum age of the glacial sequence. This paper reviews the palaeobotany and describes the faunal assemblages recovered from the Sidestrand Unio‐bed, which accumulated in a fluvial environment in a fully temperate climate with regional deciduous woodland. There are indications from the ostracods for weakly brackish conditions. Significant differences are apparent between the Sidestrand assemblages and those from West Runton, the type site of the Cromerian Stage. These differences do not result from contrasting facies or taphonomy but reflect warmer palaeotemperatures at Sidestrand and a much younger age. This conclusion is suggested by the higher proportion of thermophiles at Sidestrand and the occurrence of a water vole with unrooted molars (Arvicola) rather than its ancestor Mimomys savini with rooted molars. Amino acid racemisation data also indicate that Sidestrand is significantly younger than West Runton. These data further highlight the stratigraphical complexity of the ‘Cromerian Complex’ and support the conventional view that the Happisburgh Till was emplaced during the Anglian rather than the recently advanced view that it dates from MIS 16. Moreover, new evidence from the Trimingham lake bed (Sidestrand Cliff Formation) above the youngest glacial outwash sediments (Briton's Lane Formation) indicates that they also accumulated during a Middle Pleistocene interglacial – probably MIS 11. All of this evidence is consistent with a short chronology placing the glacial deposits within MIS 12, rather than invoking multiple episodes of glaciation envisaged in the ‘new glacial stratigraphy’ during MIS 16, 12, 10 and 6. Copyright © 2009 John Wiley & Sons, Ltd.

The earliest record of human activity in northern Europe

The colonization of Eurasia by early humans is a key event after their spread out of Africa, but the nature, timing and ecological context of the earliest human occupation of northwest Europe is uncertain and has been the subject of intense debate. The southern Caucasus was occupied about 1.8 million years (Myr) ago, whereas human remains from Atapuerca-TD6, Spain (more than 780 kyr ago) and Ceprano, Italy (about 800 kyr ago) show that early Homo had dispersed to the Mediterranean hinterland before the Brunhes-Matuyama magnetic polarity reversal (780 kyr ago). Until now, the earliest uncontested artefacts from northern Europe were much younger, suggesting that humans were unable to colonize northern latitudes until about 500 kyr ago. Here we report flint artefacts from the Cromer Forest-bed Formation at Pakefield (52 degrees N), Suffolk, UK, from an interglacial sequence yielding a diverse range of plant and animal fossils. Event and lithostratigraphy, palaeomagnetism, amino acid geochronology and biostratigraphy indicate that the artefacts date to the early part of the Brunhes Chron (about 700 kyr ago) and thus represent the earliest unequivocal evidence for human presence north of the Alps.

Implications of a Middle Pleistocene ice‐wedge cast at Trimingham, Norfolk, eastern England

AbstractA wedge exposed at Trimingham, northeast Norfolk, UK, in 1998 is interpreted as an ice‐wedge pseudomorph indicating that permafrost was present in the surrounding Cromer Forest‐bed Formation sediments. The wedge is overlain by North Sea Drift Formation (NSDF) glacial sediments, demonstrating that the associated ice sheet deposited till in either a terrestrial or an extremely shallow glaciolacustrine/marine environment. This conclusion supports those who believe that this ice sheet was, at least initially, terrestrial at this location. If the wedge is stratigraphically equivalent to the early Anglian soil stratigraphic unit, the Barham Soil, then none of the NSDF tills can be older than the Anglian/Elsterian Stage (MIS 12). Copyright © 2002 John Wiley & Sons, Ltd.

The mammalian faunas of Pakefield/Kessingland and Corton, Suffolk, UK: evidence for a new temperate episode in the British early Middle Pleistocene

It has been recognised for some time that early Middle Pleistocene mammal faunas in Britain can be divided into an earlier group with Mimomys savini (e.g. West Runton Freshwater Bed—WRFB), and a later group with Arvicola terrestris cantiana (Boxgrove, Westbury, Ostend), representing two or more temperate/interglacial stages. On the basis of the available early Middle Pleistocene non-marine molluscan faunas, Meijer and Preece (in: C. Turner (Ed.), The Early Middle Pleistocene in Europe, Balkema: Rotterdam, 1996, pp. 53–82.) and Preece (Quaternary Science Reviews 20 (2001)) recognised three biostratigraphic groups, representing at least three temperate stages. These are largely compatible with the vertebrate faunas, but new evidence presented here strongly indicates that Pakefield/Kessingland represents an additional, hitherto unrecognised temperate stage with Mimomys savini, younger than the WRFB but older than Little Oakley, Boxgrove and Westbury.New exposures and finds from the Cromer Forest-bed Formation at Pakefield, Suffolk have prompted a fresh look at the palaeontology of Pakefield/Kessingland and also Corton, which has a similar lithostratigraphic and biostratigraphic sequence. The large-mammal fauna (at least in part pollen substage II) includes Hippopotamus sp., Palaeoloxodon antiquus, and Megaloceros dawkinsi—none of which has so far been found in the WRFB—strongly suggesting that the Suffolk sites represent a distinct stage. Further, no records of ‘southern’ European plant, invertebrate or vertebrate taxa have been found in the WRFB, whereas the plants Trapa natans and Salvinia natans—indicating summers warmer than now—are known from Pakefield/Kessingland and Corton, providing corroborative evidence for a stage distinct from the Cromerian s. s.

The early Middle Pleistocene vertebrate fauna from Little Oakley, Essex

The Little Oakley channel has provided one of very few stratified early Middle Pleistocene vertebrate faunas from the British Isles. This study is based both on material recovered by S. H. Warren in 1939, and new material excavated in 1982-87. 982-87. The vertebrate fauna is entirely consistent with a temperate climate and vegetation, in keeping with palaeobotanical and invertebrate evidence from the site. Mammals include taxa indicative of both woodland (e.g. Apodemus sylvaticus, Sus scrofa ), and more open areas (e.g. Equus sp., Sorex minutus ). At least 12 species of freshwater fishes have been identified, including the first British Pleistocene records of carp ( Cyprinus carpio ), freshwater burbot ( Lota lota ), and probably zander ( Stizostedion sp.). The herpetofauna includes the earliest dated British record of European pond tortoise ( Emys orbicularis ), which together with the fish fauna indicates fully interglacial conditions. The early giant deer Megaloceros verticornis and probably M. dawkinsi are recorded for the first time in Britain outside the Cromer Forest-bed Formation. These species, together with the ancestral water vole Mimomys savini , are of considerable stratigraphic significance, strongly supporting an age for the channel later than Pastonian but pre-dating faunas 2 and 3 of Westbury-sub-Mendip.