Reconnaissance mapping of the UK’s continental shelf and slope by the British Geological Survey has led complete cover at a scale of 1:250 000 illustrating the Quaternary geology. The maps and accompanying reports give a summary of the characteristics of its component stratigraphic units.
The mapping has revealed that middle Pleistocene, late Pleistocene or Holocene sediments rest unconformably on pre-Quaternary deposits across much of the continental shelf. In the North Sea Basin, pre-Anglian deposits are thin or absent for up to 100 km east of the present coastline, although they are many hundreds of metres thick locally along the international median line. North and west of Scotland and southwest of England, pre-Anglian deposits are restricted to the outer shelf and continental slope. They probably also occur in a shallow basin extending from beneath the centre of St. George’s Channel into the south Irish Sea.
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.