Upper Jurassic (Callovian–Portlandian)
Given the great historical interest in the stratigraphical distribution of ostracods in Britain and the fact that they were long known to occur in rock-forming abundance in the Upper Jurassic-Lower Cretaceous ‘Purbeckian’ non-marine facies, the neglect of British Upper Jurassic marine ostracods is surprising. Nineteenth and early 20th century British workers showed little interest in the Upper Jurassic and, as discussed later, it was continental workers who were pioneers in this field at home in Germany and France, and who later initiated work on British sequences. Ostracods are both common and diverse in British Upper Jurassic marine sediments, and, although the following chapter can only provide an overview of the the most important taxa, it is hoped that it will encourage further investigation of spatial and temporal distribution patterns, especially including offshore sequences, to develop a more holistic view of Late Jurassic oceanographical and climatological environmental conditions.
Figures & Tables
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.