During the revolution in earth science that has taken place in recent years, studies of the North Atlantic ocean floor and of Iceland have played an increasingly significant role. Icelandic geoscientists have followed, and taken part in, these studies with a keen interest; one of the first tasks of the Geoscience Society of Iceland was to organize an Icelandic symposium on "Iceland and Mid-Ocean Ridges" in 1967. At the suggestion of Dr. G. Pfuason, the Society and various local research institutions formed in 1972 an Organizing Committee for an international meeting on earth science. It was decided that it should be devoted to examining the various expressions of geo~namical forces in the North Atlantic area, in particular at the ocean ridges passing through Iceland. Apart from the scientific content of such a meeting, the organizers also felt it was highly important for scientists from both sides of the Atlantic to meet in Iceland, to become acquainted with recent progress in earth science research there and to coordinate their future research projects in the area. The meeting was held in Reykj avik 1 - 7 July, 1974, and was followed by field trips in Iceland. Generous financial support from the NATO Scient'ific Affairs Division, the Inter-Union Com mission on Geodynamics, and many other sources, is gratefully acknowledged.

This book provides a summary of geodynamic results from Iceland that presently are found in a great number of scientific articles, but have not been collected before in a book. The ever increasing number of scientists interested in geology and geophysics of Iceland should find the book a "must" to gain knowledge about previous work and the status of knowledge about Iceland.

Recently, recognition of the potential role of large igneous provinces in affecting ocean and atmosphere systems and biotic evolutionary pathways has lead to increased interest in this province. This has been further stimulated by the expansion in the search for oil and gas in Mesozoic and Tertiary sediments along the NE Atlantic Margin. An improved understanding of the interaction between igneous and sedimentary processes is vital for the identification of potential hydrocarbon resources.

The volcanic island of Iceland is a unique geological place due both to its position in the middle of the Atlantic Ocean and its repeated glaciations. It has been an accurate recorder of geodynamic and regional climatic evolutions for at least the last 15 million years. This book traces the history of Iceland, which is linked to the opening of the North Atlantic and the reactivation of the ancient suture of the Iapetus Ocean. It gives a view of climate evolution that is partly controlled by the dynamics of the ocean floor and analyzes the movement of the Jan Mayen tectonic plate and the progressive insularization of the Greenland–Faroe Ridge, which gave birth to Iceland. It also tries to understand the formation and migration of the deep Iceland hotspot and the lava flows that have, for millions of years, shaped this island. This book brings together the internal and external geodynamics of our planet to understand how Iceland functions and its role as a recorder of the paleoclimatic evolution of the Northern Hemisphere.

This trip backward in time capsulizes in a general way the geologic development of the area that is now northern Alaska. The Cretaceous through Recent history is predominantly one of erosion of the ancient Brooks Range and filling of the Colville Geosyncline under processes like those in Operation today. All the rocks older than Jurassic, however, were deposited far from their present sites. One of the intriguing tectonic puzzles involves the geographic positions and relative timing of events that occurred during the orogeny that built the Brooks Range. I suggest that pre-Cretaceous deposition took place far to the north along the western margin of the Caledonides. Subsequently, the region that is now northern Alaska moved southward and impinged upon a northward moving plate, or plates, from the Pacific region. Interactions between these two major parts of the earth's crust produced the Brooks Range during the Jurassic. Later developments reflect continuing readjustments of the northern third of of thrust Alaska as southward movement was dissipated in diverse systems faulting and lateral displacement. ACKNOWLEDGMENTS I am indebted to many colleagues who, during the past 30 years, shared with me the excitement and pleasures of exploring the geology of northern Alaska. Among these are W. P. Brosge, H. N. Reiser, R. L. Detterman, A. K. Armstrong, A. L. Bowsher, E. G. Sable, I. L. Tailleur, C. G. Mull, M. D. Mangus, A. H. Lachenbruch, M. C. Lachenbruch, R. L. Morris, C. J.