This paper examines recent advances in understanding of the Tertiary evolutionary geomorphology of the southern England Chalklands, a subject of continuing controversy despite over a century of investigation. It begins by briefly outlining the classic Wooldridge and Linton model and discussing the many lines of criticism. Particular attention is paid to the explanation of discordant drainage and numerous lines of evidence are presented to explain why the 'superimposition model' has been rejected in favour of an explanation involving the development of anteconsequents. Attention is then directed to the new models of evolution advanced in the early 1980s which placed heavier emphasis on Palaeogene denudation and pulsed tectonism. These models are compared and contrasted, and attention focused on the growing recognition that the fundamental erosional surface is an etchplanated Summit Surface originating in the Palaeogene rather than a peneplanated surface developed during the Miocene and Pliocene. Significant developments of the last fifteen years are then reviewed -the establishment of inversion tectonics, lithostratigraphical division of the Chalk, apatite fission-track dating of uplift episodes and new information on the extent of the late Pliocene Red Crag incursionand combined to produce a new evolutionary sequence which differs from previous interpretations in a number of regards. First, the concept of structural compartmentalization into morphotectonic regions removes the need for uniformity of evolution and indicates that uplift could have been variable in time and space, thereby removing the problems caused by continual adherence to the concept of mid-Tertiary tectonism. Second, the growing evidence for Pleistocene differential uplift of at least 200 m is considered. Third, an explanation of the so-called Plio-Pliocene marine bench involving modified etchplanation is advanced. The paper concludes with a discussion of remaining uncertainties.

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Geomorphological mapping in site investigations for highway engineering is proving to be a rapid means of obtaining much relevant information about ground conditions. Such mapping requires the recognition of both the origin of surface features and the geological processes that still influence them. In addition information about materials is recorded and inferences made about their extent.The paper identifies eight aims of a geomorphological survey for highway engineering and discusses these in the context of small-scale maps and large-scale plans. The latter are illustrated by case studies from Nepal and South Wales.The review identifies the established applications of geomorphological mapping to site investigation and concludes that further work can usefully be directed towards a broadening of the geomorphological content of site investigation.

Discusses the 1984 study review by the Department of the Environment of existing knowledge regarding landslipping in Great Britain. Reviews the background to the study and presents some of the general results. Concludes that knowledge of landslide distribution, character and significance remain surprisingly poor, that old (ancient) landslides are much more widely distributed in the landscape than previously thought, and that such old features present an important potential threat to buildings and structures because they can be reactivated if disturbed. Suggests that heightened perception of landslide hazard will lead to greater consideration of ground stability prior to developments, including increased use of various types of survey techniques that exist, and delimit areas of actual and potential instability.