The geologic history of the Pacific Northwest is as unique as the region itself. Created via tectonic plate movements and accretionary events, the original terranes were subsequently covered by sedimentary layers, ash, lavas, and glacial debris. These processes, begun millions of years ago, continue to affect the area, as seen in the eruption of Mount St. Helens and catastrophic Japanese tsunamis created by earthquakes in the Pacific Northwest. Understanding of the regions geology has led to new insight in volcanic eruption prediction, disaster preparedness, the environmental effects of mining, and urban development as it relates to geologic hazards. The Orrs detailed and informative writing style appeals to those with geologic training as well as beginners with an interest in the region. Each chapter covers a specific subregion, allowing for maximum flexibility both in the classroom and for the casual reader. The authors central theme that continental plate tectonics are the fundamental processes of Northwest geologic history permeates throughout the book.

This book reviews advances in understanding of the past ca. two million years of Earth history - the Quaternary Period - in the United States. It begins with sections on ice and water - as glaciers, permafrost, oceans, rivers, lakes, and aquifers. Six chapters are devoted to the high-latitude Pleistocene ice sheets, to mountain glaciations of the western United States, and to permafrost studies. Other chapters discuss ice-age lakes, caves, sea-level fluctuations, and riverine landscapes. With a chapter on landscape evolution models, the book turns to essays on geologic processes. Two chapters discuss soils and their responses to climate, and wind-blown sediments. Two more describe volcanoes and earthquakes, and the use of Quaternary geology to understand the hazards they pose. The next part of the book is on plants and animals. Five chapters consider the Quaternary history of vegetation in the United States. Other chapters treat forcing functions and vegetation response at different spatial and temporal scales, the role of fire as a catalyst of vegetation change during rapid climate shifts, and the use of tree rings in inferring age and past hydroclimatic conditions. Three chapters address vertebrate paleontology and the extinctions of large mammals at the end of the last glaciation, beetle assemblages and the inferences they permit about past conditions, and the peopling of North America. A final chapter addresses the numerical modeling of Quaternary climates, and the role paleoclimatic studies and climatic modeling has in predicting future response of the Earth's climate system to the changes we have wrought.

Bear Lake is located 100 km northeast of Salt Lake City and lies along the course of the Bear River, the largest river in the Great Basin. The lake, which is one of the oldest extant lakes in North America, occupies a tectonically active half-graben and contains hundreds of meters of Quaternary sediment. This volume is the culmination of more than a decade of coordinated investigations aimed at a holistic understanding of this long-lived alkaline lake in the semiarid western United States. Its 14 chapters, with 20 contributing authors, contain geological, mineralogical, geochemical, paleontological, and limnological studies extending from the drainage basin to the depocenter. The studies span both modern and paleoenvironments, including a 120-m-long sediment core that captures a continuous record of the last two glacial-interglacial cycles.

Landscape Evolution of Continental-Scale River Systems: A Case Study of North America's Pre-Pleistocene Bell River Basin provides a detailed case study and complete analysis of this continental-scale North American paleo-river system. The book uses detrital zircon provenance data to link incision of the Grand Canyon to deposition of its erosional products in a giant drowned delta in the Labrador Sea, in the context of sedimentary source-to-sink processes and Plio-Pleistocene continental drainage changes. The case study describes the tectonic changes in this continental-scale paleo-river system, with global implications, and contrasts this system to other continental-scale river systems around the world. This book is a valuable reference for postgraduate students, academics and researchers in the fields of geology, fluvial geomorphology and other geosciences. Readers will be able to use this detailed case study to better understand the implications for how active tectonics of headwaters regions influence delta deposition in continental-scale river systems around the world. - Details the landscape evolution of a continental-scale paleo-river system using detrital zircon geochronology with fluvial processes - Provides a multidisciplinary case study with applications to other continental-scale river systems around the world - Compares and contrasts the Bell river to the Amazon and uses these examples as analogs to discuss other systems

This volume focuses on the geometry, kinematic development, and origin of regional segmentation structures within the basin and range province of Western North America. Contributions range from analysis of individiual structures to broad regional syntheses, including a map of basin and range structures and tilt domains. Several papers discuss the implications of regional segmentation structures in assessing seismic hazards, hydrocarbon and mineral resources, and ground-water supplies.