The most recent glacial-interglacial transition of the late Pleistocene ice age was accompanied by an increase in globally averaged ice-equivalent eustatic sea level of ∼120 m. This increase in sea level occurred over a period of ∼10,000 yr and was accompanied by highly significant regional inundations of the land by the sea as well as by significant regional emergence of the land from the sea in the initially ice-covered regions. These migrations of the coastline can be accurately predicted given only an assumed known history of the deglaciation of the continents. An especially interesting aspect of the suite of physical interactions involved in the global process of glacial isostatic adjustment concerns the influence of variations in the Earth's rotation on the local histories of relative sea level, which may be inferred on the basis of radiocarbon dating of suitable sea-level index points. The observed variability in sea level may be interpreted in terms of fundamentally important climatological and solid Earth geophysical properties of Earth System processes that govern system evolution.

Abstract This chapter provides a rather modest introduction to the extensive Quaternary data base which currently exists and to the geophysical models which have been developed to interpret these data; it is clear that an active interplay between theory and observation is desirable. The Quaternary geological data can be brought to bear upon several vital geodynamic issues, including the question of the variation of mantle viscosity with depth, the question of the thickness of the continental lithosphere, and the question of the nature of the discontinuities in elastic parameters which are observed seismically to occur at depths of 420 and 670 km in the earth. All of these questions are of importance in attempting to understand the nature of the convective circulation in the mantle which is responsible for continental drift and seafloor spreading; the Quaternary geological record has begun to provide crucial information with which it will be possible in future to further refine our understanding. This limited space does not allow all areas of Quaternary geodynamic research to be dealt with adequately. Some aspects not dealt with are: (1) the manner in which the isostatic adjustment process may serve to cause earthquakes by the reactivation of slip on old faults located near the ice sheet margin; (2) the manner in which the grauitationally self-consistent model of relative sea level variation may be employed to filter the modern tide gauge data to reveal more clearly the presence of any currently ongoing “eustatic” component of sea level rise due to, for example