Coastal Lowlands by virtue of their position across the boundary of land and sea belong to the earth's most dynamic systems. This is true in the physical, i. e. geological and biological, as much as in the cultural and social sense. Although the nearness to the sea was and still is fraught with danger coastal lowlands have always attracted human interest, providing challenging opportunity, holding the promise of profitable enterprise. Coastal lowlands, especially where rivers enter the region, are the cradles of great civilisations and there, of old, populations reached highest densities. As an example, Dutch history is a tale of human struggle and endeavour with and against the sea. Dutch 'low landers' wrestled their land from the sea, in turn the sea forged a nation of independent fishermen, navigators, farmers and traders who built their towns and ships at the borders of the North and Zuyder Seas. As lowlands subside and sea level rises, apparently these days at an increasing rate, concern about this environment world-wide is also rising. It certainly was appropriate and timely for the Royal Geological and Mining Society of the Netherlands when celebrating its 75th birthday to organize and call together a symposium, focussing attention on the geology and geotechnology of coastal lowlands; geology to better understand their formation and evolution, geotechnology to better manage and harvest resources as much as protect a unique and crucial environment.

Man s intensifying use of the Earth s habitat has led to an urgent need for scientifically advanced geo-prediction systems that accurately locate subsurface resources and forecast the timing and magnitude of earthquakes, volcanic eruptions and land subsidence.

As advances in the earth sciences lead to process-oriented ways of modeling the complex processes in the solid Earth, the papers in this volume provide a survey of some recent developments at the leading edge of this highly technical discipline. The chapters cover current research in predicting the future behavior of geologic systems as well as the mapping of geologic patterns that exist now in the subsurface as frozen evidence of the past. Both techniques are highly relevant to humanity s need for resources such as water, and will also help us control environmental degradation.

The book also discusses advances made in seismological methods to obtain information on the 3D structure of the mantle and the lithosphere, and in the quantitative understanding of lithospheric scale processes. It covers recent breakthroughs in 3D seismic imaging that have enhanced the spatial resolution of these structural processes, and the move towards 4D imaging that measures these processes over time.

The new frontier in modern Earth sciences described in this book has major implications for oceanographic and atmospheric sciences and our understanding of climate variability. It brings readers right up to date with the research in this vital field."

The contributions to this book follow a topical trend. In several geophysical fields evidence is accumulating concerning the deviation of the earth's structure from radial symmetry. Seismology provides the most adequate resolution for revealing the earth's lateral inhomogeneity on a global to local scale. Lateral structure in the density distribution is also manifest in the earth's gravity field and in the geoid. Asphericity in physical parameters, generally supposed only to vary with the vertical coordinate, has a profound influence on geodynamics. The effects of these deviations from spherical symmetry concern in particular convection theory, post-glacial rebound and the dynamics of the lithosphere and upper mantle in general. At the 16th International Conference on Mathematical Geophysics which was held in Oosterbeek, the Netherlands, in 1986, the need was felt to present the state of the art. Several prospective authors were found interested to contribute to the present book. This Oosterbeek conference was one in a long series of topical conferences starting with the Upper Mantle Project Symposia on Geophysical Theory and Computers in the 1960s, and thence their successors, the conferences on Mathematical Geophysics, until the present.

The contributions to this book follow a topical trend. In several geophysical fields evidence is accumulating concerning the deviation of the earth's structure from radial symmetry. Seismology provides the most adequate resolution for revealing the earth's lateral inhomogeneity on a global to local scale. Lateral structure in the density distribution is also manifest in the earth's gravity field and in the geoid. Asphericity in physical parameters, generally supposed only to vary with the vertical coordinate, has a profound influence on geodynamics. The effects of these deviations from spherical symmetry concern in particular convection theory, post-glacial rebound and the dynamics of the lithosphere and upper mantle in general. At the 16th International Conference on Mathematical Geophysics which was held in Oosterbeek, the Netherlands, in 1986, the need was felt to present the state of the art. Several prospective authors were found interested to contribute to the present book. This Oosterbeek conference was one in a long series of topical conferences starting with the Upper Mantle Project Symposia on Geophysical Theory and Computers in the 1960s, and thence their successors, the conferences on Mathematical Geophysics, until the present.