Overview of the geology and tectonic evolution of Alaska
In this chapter we present a brief overview of major aspects of the geology and tectonic evolution of Alaska. Our objective has been to incorporate the lithologic, structural, paleontologic, geophysical, and paleomagnetic data presented in this volume and elsewhere into a series of generalized interpretive maps that depict our version of the Phanerozoic tectonic evolution of Alaska. Where necessary, adjacent areas of Canada and the conterminous United States are discussed and shown on the maps. Many stratigraphic and tectonic relations germane to Alaska are present in those regions and some terranes now in Alaska were derived from regions to the south.
Our interpretation emphasizes evaluation of the data according to plate tectonics models and the concept that much of Alaska is a collage of tectonostratigraphic terranes that have been displaced to varying degrees relative to each other and to the North American craton. Many problems remain, however, and alternative interpretations have been proposed by others for virtually every major aspect of the model presented here. We hope that this synthesis will highlight crucial areas for future research in order to resolve ambiguities among the array of data sets and analog models.
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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.