The Micropalaeontological Society

Annual General Meeting 2003

The Annual General Meeting was held on 26th November at University College London.

Following Society business, two talks were presented.

The use of reworked palynomorphs in the provenance analysis of the Crag Group (Pleistocene) and the pre-Devensian glacial deposits of East Anglia

J.B. Riding1, J. Rose2, R.J.O. Hamblin1, B.S.P. Moorlock1, S.J. Booth1, J.R. Lee2 and S. Pawley2
1British Geological Survey, Keyworth, Nottingham, Nottinghamshire
2Department of Geography, Royal Holloway, University of London, Egham, Surrey

Allochthonous palynomorphs have proved extremely useful in the provenance analysis of the Crag Group and the overlying pre-Devensian glacial succession in East Anglia, southeast England. The Crag Group is dominantly fluvial and palynomorph-bearing sedimentary clasts picked up inland to the north and west, especially where the rivers were of high erosive force, can help model the paths of these major drainage elements. Likewise, the palynological content of Till sheets can also provide valuable evidence of provenance. In both the Crag Group and the Till succession, Carboniferous and Jurassic palynomorphs may be especially common, with lesser proportions of Cretaceous and Palaeogene elements. Palynomorphs of Silurian to Quaternary age have been observed.

Both derived palynofloras and clast lithologies from river and shallow marine sediments have been used to correlate pre-Anglian fluvial and coastal deposits in eastern England. The results are used to provide a lithostratigraphical framework for the Early and early Middle Pleistocene sediments, and to derive sedimentary models that can be linked to the tectonic and climatic processes that determined the behaviour of the geological systems. Three geological systems are recognised. i) The river Thames, which drained an area from Wales through Midland England to the Thames basin and southern East Anglia and reached the southern North Sea delta in the region of southern East Anglia. ii) The Bytham river which drained midland England and the southern Pennines and reached the southern North Sea delta in the region of north central East Anglia. iii) The Ancaster river which drained the southern Pennines and received sediment from northeast England. This river reached the sea in, and north of, northern East Anglia and contributed to some of the Cromer Forest-Bed. Each of these rivers contributed to the shallow marine sediments that formed around the eastern margin of the southern North Sea delta/estuary and are known as the Red, Norwich, and Wroxham Crag formations.

Similarly, the study of allochthonous palynomorphs can be effectively applied to the provenance of the pre-Devensian glacial deposits of Norfolk. Traditionally these deposits have been divided into a Lowestoft Formation, overlying a North Sea Drift Formation, the latter including three or four tills. All were considered to be Anglian, Oxygen Isotope Stage (OIS) 12. However, detailed mapping has demonstrated that the Lowestoft Till equates to the Walcott Till or Second Cromer Till, the second of the North Sea Drift tills. The deposits underlying the Lowestoft Till are now termed the Happisburgh Formation and were derived from northern Britain and the North Sea. The Lowestoft Formation is overlain by the Bacton Green or Third Cromer Till, for which derivation from northern Britain and the North Sea is also proposed; no Scandinavian erratics have been found in this till. The Bacton Green Till is overlain by the Overstrand Formation. This includes both sandur deposits (Briton’s Lane Member) and till (Stody Member), both of which are dominated by coarse, rounded flints. Unlike the earlier formations, the Overstrand Formation reveals constructional geomorphology and contains Scandinavian erratics, and an OIS 6 age is proposed for this glaciation, corresponding to the major glaciation in the Netherlands.

Micropalaeontology in the service of archaeology: advances in Quaternary biostratigraphy and palaeoenvironmental analysis
using foraminifera and ostracods

J.E. Whittaker1, Dave Horne2 & Bob Wynn Jones3
1Department of Palaeontology, Natural History Museum, Cromwell Road, London
2Department of Geography, Queen Mary College, University of London
3BP Exploration, Sunbury-on-Thames, Middlessex

It all started with Boxgrove! Traditionally, palynology had been the foremost tool in the micropalaeontological interpretation of the Quaternary. At the world-famous Boxgrove archaeological site (of Cromerian age), West Sussex, however, poor preservation of palynomorphs resulted in a need to consider other options; consequently I was asked, about ten years ago, to assess the potential of ostracods and foraminifera as palaeoenvironmental proxies and dating tools at Boxgrove. Results were encouraging and led to further requests to analyse calcareous microfossils from other archaeological sites, including the Aldingbourne, Brighton-Norton, and Selsey raised beaches in Sussex, as well as further afield. Soon, however, it was realised that taxonomic nomenclature in both microfossil groups needed substantial revision if they were to be used effectively to circumvent the loss of valuable climatic, environmental and biostratigraphic information due to misidentifications. Case histories from several UK sites are presented here and provide examples of successes resulting from exciting new discoveries, as well as some cautionary tales. A case is made for a renewed effort to establish a standard taxonomic database of Quaternary ostracods and foraminifera that extends well beyond the boundaries of NW Europe. The need for a harmonisation of biological and palaeontological classifications, particularly of freshwater ostracods, is also highlighted.