The Geology of Alaska summarizes the onshore and offshore geology, tectonic evolution, and mineral resources of Alaska and the adjacent continental margin. The volume was prepared at a particularly appropriate time because it follows a period during which there has been an explosive increase in the amount, quality, and regional coverage of earth science data collected in Alaska and because the unifying concepts of plate tectonics and accretionary terranes have become available as a framework for interpreting the data. These new concepts have led to recognition that all of Alaska, except possibly for one area that underlies less than one percent of the state, consists of lithotectonic terranes (also referred to as “suspect” or “tectonostratigraphic” terranes) that have been added to, displaced from, and/or rotated to varying degrees relative to autochthonous parts of the continental margin (Silberling and others, this volume, Plate 3). Thus, a first-order division of the geology of Alaska can be made into (1) the small area of probable autochthonous rocks in east-central Alaska; (2) terranes underlain by known or probable pre-Late Proterozoic continental crust that were part of the North American miogeocline; and (3) terranes, flysch basins, and overlap assemblages that have either been added to, or built along, the south and west margins of the miogeoclinal assemblages in a belt 550 to 700 km wide (Fig. 1). Much of the geologic research in Alaska during the past 15 years has focused on defining these lithotectonic terranes on the basis of their biostratigraphic, magmatic, metamorphic, structural
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You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.