Marine deposition dominated the Early Pleistocene and parts of the early Middle Pleistocene. The region experienced glaciation on at least two occasions; during the Anglian and Late Devensian. There may also be some localities that show evidence of additional glacial episodes (Gibbard et al. 1991a, 1992). Evidence of fluvial activity is significant, with major reorganization of the drainage system as a result of glaciation during the Anglian.
Early Pleistocene deposits are mainly marine in origin, and were deposited at the margins of the southern North Sea basin. The Red Crag and Norwich Crag Formations occur in the southern and eastern parts of East Anglia. Coastal sections together with boreholes through the deeper Crag basins provided reference sections for Early Pleistocene stages defined by Mitchell et al. (1973). These provide lithostratigraphical and biostratigraphical information for correlation of the British sequence with those of the Netherlands (Gibbard et al. 1991b). These correlations reveal a gap of about I Ma in the British sequence.
Figures & Tables
A revised correlation of Quaternary deposits in the British Isles
Realization that continental records of Quaternary rocks were more complex that hitherto believed came with the re-interpretation of oxygen isotope stratigraphy in the late 1960s and early 1970s. This necessitated a comprehensive re-evaluation that has been assisted by the emergence of new geochronological methods for terrestrial as well as land-sea correlations. The current state of such correlations is presented in this revised set of proposals for correlations in England, Ireland, Scotland and Wales, which also includes the Quaternary geology of the continental shelf. Correlation with the global standard of oxygen isotope stratigraphy enables the significance of British lithostratigraphical units to be appreciated in a wider context that includes the evolution of the climate system on the margin of the northeast Atlantic Ocean. It thus provides timely British data for the international palaeoceanographical and palaeoclimatological community and the correlations proposed are primarily on Milankovitch timescales. But their appearance coincides with the early stages of a paradigm shift to the search for both terrestrial and land-sea correlation on millennial timescales and then on centennial and decadal ones. This is the first of many similar terrestrial and land-sea correlations.