The marine sediments of the Lower Cretaceous are well represented across England from Yorkshire, through Lincolnshire, Norfolk, across the country to Devon, Dorset, the Isle of Wight and around the Weald in SE England (Fig. 1). All but the lower part of the Ryazanian is represented, and much is developed in lithologies that are suitable for the preservation and extraction of Ostracoda. The most significant section is that found in Filey Bay, North Yorkshire where the Speeton Clay Formation crops out and provides access to most of the Lower Cretaceous. However, this is a difficult section to work owing to much landslipping and local faulting; in addition, some horizons, particularly those with high iron content, prove to be barren. The numerous publications of Neale and Kaye (see later) show, however, that good ostracod assemblages may be won from this section. Equivalent levels are found in Lincolnshire where the Tealby Clay, Skegness Clay and Sutterby Marl formations have all proved ostracod faunas. After the Early Aptian transgression, marine conditions were established in southern England, which resulted in the deposition of the Atherfield Clay Formation, but much of the overlying Lower Greensand is clastic in nature and does not preserve ostracods well; the latest Aptian and Early Albian are poorly served for recovery of ostracods. The Middle and Upper Albian Gault Clay Formation in the south provides exquisite preservation of the finest details in most specimens, and although the section at Copt Point, Folkestone, Kent suffers from some slipping it
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Ostracods in British Stratigraphy
This book charts the stratigraphical distribution of ostracods in the Cambrian to Pleistocene deposits of Britain and outlines their utility for dating and correlating rock sequences, as well as indicating aspects of their palaeoenvironmental and palaeogeographical significance. These small bivalved crustaceans are the most abundant arthropods in the fossil record. Indeed, the stratigraphy of Britain, which embraces many type-sequences, provides a particularly rich and full record of them, from at least the basal Ordovician, and from the British Cambrian there is a biostratigraphy based on their ‘relatives’, the bradoriids and phosphatocopids. Ostracod distributions demonstrate the ecological success story of the group, occupying as they do marine, non-marine and even ‘terrestrial’ habitats. Written by current specialists in the field, this book is an authoritative account and will be welcomed by all micropalaeontologists and applied geologists in the industrial and academic world alike. It is richly illustrated with over 80 plates of electron micrographs and specially drawn maps, diagrams and range-charts.