This book is the proceedings of the 11th Kongsberg seminar, held at the Norwegian Mining Museum in the city of Kongsberg, about 70 km Southwest of Oslo. The Kongs berg district is known for numerous Permian vein deposits, rich in native silver. Mining activity in the area lasted for more than 300 years, finally ceasing in 1957. The first eight Kongsberg seminars, organized by professor Arne Bj0rlykke, now director of the Norwegian Geological Survey, were focused on ore-forming processes. These seminars have always been a meeting point for people with a variety of geological backgrounds. Since 1995, the Kongsberg seminars have focussed on geological processes, rather than on specific geological systems, and the selection of invited speakers has been strongly influenced by their interest in the dynamics of geological systems. In 1995 and 1996, various aspects of fluid flow and transport in rocks, were emphasized. The first "Kongsberg proceedings" (of the 1995 seminar) published by Chapman and Hall (Jamtveit and Yardley, 1997) contained 17 chapters dealing with a wide range of topics from field based studies of the effects of fluid flow in sedimentary and metamorphic rocks to computer simulations of flow in complex porous and fractured media. In 1997, the focus was changed to growth, and dissolution processes in geological systems."

During the past decade interest in the formation of complex disorderly patterns far from equilibrium has grown rapidly. This interest has been stim ulated by the development of new approaches (based primarily on fractal geometry) to the quantitative description of complex structures, increased understanding of non-linear phenomena and the introduction of a variety of models (such as the diffusion-limited aggregation model) that provide paradigms for non-equilibrium growth phenomena. Advances in computer technology have played a crucial role in both the experimental and theoret ical aspects of this enterprise. Substantial progress has been made towards the development of comprehensive understanding of non-equilibrium growth phenomena but most of our current understanding is based on simple com puter models. Pattern formation processes are important in almost all areas of science and technology, and, clearly, pattern growth pervades biology. Very often remarkably similar patterns are found in quite diverse systems. In some case (dielectric breakdown, electrodeposition, fluid-fluid displacement in porous media, dissolution patterns and random dendritic growth for example) the underlying causes of this similarity is quite well understood. In other cases (vascular trees, nerve cells and river networks for example) we do not yet know if a fundamental relationship exists between the mechanisms leading the formation of these structures.

This book is the proceedings of the 11th Kongsberg seminar, held at the Norwegian Mining Museum in the city of Kongsberg, about 70 km Southwest of Oslo. The Kongs berg district is known for numerous Permian vein deposits, rich in native silver. Mining activity in the area lasted for more than 300 years, finally ceasing in 1957. The first eight Kongsberg seminars, organized by professor Arne Bj0rlykke, now director of the Norwegian Geological Survey, were focused on ore-forming processes. These seminars have always been a meeting point for people with a variety of geological backgrounds. Since 1995, the Kongsberg seminars have focussed on geological processes, rather than on specific geological systems, and the selection of invited speakers has been strongly influenced by their interest in the dynamics of geological systems. In 1995 and 1996, various aspects of fluid flow and transport in rocks, were emphasized. The first "Kongsberg proceedings" (of the 1995 seminar) published by Chapman and Hall (Jamtveit and Yardley, 1997) contained 17 chapters dealing with a wide range of topics from field based studies of the effects of fluid flow in sedimentary and metamorphic rocks to computer simulations of flow in complex porous and fractured media. In 1997, the focus was changed to growth, and dissolution processes in geological systems."