A new approach to the relief of Great Britain: I. The machine-readable database

We describe a simple, if fairly large, database of relief and geology for Great Britain and the surrounding shelf based on the kilometre squares of the National Grid. The area covered is 560,000 km2, 319,490 km2 classified as sea and 240,510 km2 as land (squares which included the coastline were classed as land). The database affords a new approach to establishing the importance of rock resistance to erosion as a factor affecting the form of the present land surface, the legacy of older tectonic movements, and the role of neotectonics. It can be used to test existing hypotheses, or propose new ones, which can then be tested against other evidence. Initial data on land/shelf contrasts are presented. The current coastal zone is found to be a sector of relatively abrupt transition from shelf depths between −60 and −70 m, to land elevations exceeding an average of over 100 m, even within a few kilometres of the coast. This transition zone is attributed to the isostatic buoyancy of a land area steadily unloaded by denudation and attacked by the transgressing sea as water levels rise after each glacial stage. The database is a novel and powerful way to tackle some fundamental aspects of the evolution of the relief of Great Britain and further papers will explore issues such as relative rock resistance and evidence for neotectonic movement.