Rare Earth Frontiers is a work of human geography that serves to demystify the powerful elements that make possible the miniaturization of electronics, green energy and medical technologies, and ...essential telecommunications and defense systems. Julie Michelle Klinger draws attention to the fact that the rare earths we rely on most are as common as copper or lead, and this means the implications of their extraction are global. Klinger excavates the rich historical origins and ongoing ramifications of the quest to mine rare earths in ever more impossible places. Klinger writes about the devastating damage to lives and the environment caused by the exploitation of rare earths. She demonstrates in human terms how scarcity myths have been conscripted into diverse geopolitical campaigns that use rare earth mining as a pretext to capture spaces that have historically fallen beyond the grasp of centralized power. These include legally and logistically forbidding locations in the Amazon, Greenland, and Afghanistan, and on the Moon. Drawing on ethnographic, archival, and interview data gathered in local languages and offering possible solutions to the problems it documents, this book examines the production of the rare earth frontier as a place, a concept, and a zone of contestation, sacrifice, and transformation.
Approximately 12,000 years ago, at the end of the last ice age, the three kilometers of ice that covered Canada, the large European glaciers in Fennoscandia and Siberia, and many other minor glaciers ...melted quickly. The resulting meltwaters increased the depth of the world's oceans by about 110 meters. The earth's response to this redistribution of loads was one of fluid flow. By studying the way in which that flow occurred, much can be learned about the viscosity structure of the earth's mantle: that is, how the fluid properties of the earth vary with depth.
In this volume Lawrence M. Cathles III sets out to lay the theoretical foundations necessary to model the isostatic (fluid) adjustment of a self-gravitating viscoelastic sphere, such as the earth, and to use these foundations, together with geological evidence of the way the earth responded to the pleistocene land redistributions, to study the viscosity of the mantle.
The author argues that the viscosity of the entire mantle is very close to 1022poise, except for a low-viscosity channel, about 75 kilometers thick, in the uppermost mantle. This conclusion differs sharply from the common view that the earth's mantle becomes very viscous (1027poise) below a depth of about 1000 kilometers./p
Originally published in 1975.
ThePrinceton Legacy Libraryuses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These paperback editions preserve the original texts of these important books while presenting them in durable paperback editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.
Large earthquakes initiate chains of surface processes that last much longer than the brief moments of strong shaking. Most moderate‐ and large‐magnitude earthquakes trigger landslides, ranging from ...small failures in the soil cover to massive, devastating rock avalanches. Some landslides dam rivers and impound lakes, which can collapse days to centuries later, and flood mountain valleys for hundreds of kilometers downstream. Landslide deposits on slopes can remobilize during heavy rainfall and evolve into debris flows. Cracks and fractures can form and widen on mountain crests and flanks, promoting increased frequency of landslides that lasts for decades. More gradual impacts involve the flushing of excess debris downstream by rivers, which can generate bank erosion and floodplain accretion as well as channel avulsions that affect flooding frequency, settlements, ecosystems, and infrastructure. Ultimately, earthquake sequences and their geomorphic consequences alter mountain landscapes over both human and geologic time scales. Two recent events have attracted intense research into earthquake‐induced landslides and their consequences: the magnitude M 7.6 Chi‐Chi, Taiwan earthquake of 1999, and the M 7.9 Wenchuan, China earthquake of 2008. Using data and insights from these and several other earthquakes, we analyze how such events initiate processes that change mountain landscapes, highlight research gaps, and suggest pathways toward a more complete understanding of the seismic effects on the Earth's surface.
Plain Language Summary
Strong earthquakes in mountainous regions trigger chains of events that modify mountain landscapes over days, years, and millennia. Earthquake shaking can cause many tens of thousands of landslides on steep mountain slopes. Some of these sudden slope failures can block rivers and form temporary lakes that can later collapse and cause huge floods. Other landslides move more slowly, in some cases in a stop‐start fashion during heavy rains or earthquake aftershocks. Debris from these landslides can clog channels, and during heavy rainfall, the debris can be transported downstream for many kilometers with catastrophic consequences. New landslides tend to happen more frequently than usual for months to years following an earthquake because the strong ground shaking has fractured and weakened the slopes. Other effects of large earthquakes can last, in various forms, over geologic time scales. Over the past two decades, our understanding of these issues has advanced because of the detailed study of the 1999 Chi‐Chi earthquake in Taiwan and the 2008 Wenchuan earthquake in China. We compile and discuss the results of research on these and other earthquakes and explain what we have learned, what we still need to know, and where we should direct future studies.
Key Points
Coupled surface processes initiated by strong seismic shaking are important hazards in mountain landscapes
Earthquake‐induced landslides pose challenges to hazard and risk assessment, management, and mitigation
Multidisciplinary approaches further the understanding of the earthquake hazard cascade, yet challenges remain
After a great subduction earthquake, viscoelastic stress relaxation causes opposing motion of Earth's surface in the strike‐normal direction, with the dividing boundary located roughly above the ...downdip termination of the rupture. As the effect of the viscoelastic relaxation decays with time, the effect of the relocking of the megathrust becomes increasingly dominant to cause the dividing boundary to migrate away from the rupture zone, eventually leading to wholesale landward motion. The evolution of the postseismic deformation is controlled not only by mantle viscosity but also by the size of the earthquake. Large coseismic fault slip induces greater stress perturbation that takes a longer time to relax, and a greater rupture length along‐strike results in a pattern of postseismic viscous mantle flow less efficient for stress relaxation. Here we employ spherical‐Earth finite element models of Burgers rheology to quantify postseismic deformation processes for ten 8.0 ≤ Mw ≤ 9.5 subduction earthquakes. Using geodetic data as constraints, we reconstruct spatiotemporally continuous evolution of the postseismic deformation following each earthquake. We comparatively examine the “reference time” when the dividing boundary of the opposing motion passes through the map view location of the 50‐km depth contour of the subduction interface. Our results suggest a positive dependence of the reference time on earthquake size, although site‐ and/or event‐specific factors such as subduction rate, afterslip, and postseismic locking state of the megathrust also affect the evolution. Upper mantle viscosities constrained by available geodetic observations show somewhat different values between subduction zones located far from one another.
Key Points
In postseismic deformation following great subduction earthquakes, the dividing boundary of opposing motion migrates away from the trench
How fast the dividing boundary migrates, measured using a reference time, depends on Earth's viscoelastic rheology and earthquake size
Comparative modeling of ten 8.0 ≤ Mw ≤ 9.5 earthquakes suggests a positive dependence of the reference time on earthquake size
In a rapidly changing world, there is an ever-increasing need to monitor the Earth’s resources and manage it sustainably for future generations. Earth observation from satellites is critical to ...provide information required for informed and timely decision making in this regard. Satellite-based earth observation has advanced rapidly over the last 50 years, and there is a plethora of satellite sensors imaging the Earth at finer spatial and spectral resolutions as well as high temporal resolutions. The amount of data available for any single location on the Earth is now at the petabyte-scale. An ever-increasing capacity and computing power is needed to handle such large datasets. The Google Earth Engine (GEE) is a cloud-based computing platform that was established by Google to support such data processing. This facility allows for the storage, processing and analysis of spatial data using centralized high-power computing resources, allowing scientists, researchers, hobbyists and anyone else interested in such fields to mine this data and understand the changes occurring on the Earth’s surface. This book presents research that applies the Google Earth Engine in mining, storing, retrieving and processing spatial data for a variety of applications that include vegetation monitoring, cropland mapping, ecosystem assessment, and gross primary productivity, among others. Datasets used range from coarse spatial resolution data, such as MODIS, to medium resolution datasets (Worldview -2), and the studies cover the entire globe at varying spatial and temporal scales.
This is the first book to provide a comprehensive and state-of-the-art introduction to the novel and fast-evolving topic of in-situ produced cosmogenic nuclides. It presents an accessible ...introduction to the theoretical foundations, with explanations of relevant concepts starting at a basic level and building in sophistication. It incorporates, and draws on, methodological discussions and advances achieved within the international CRONUS (Cosmic-Ray Produced Nuclide Systematics) networks. Practical aspects such as sampling, analytical methods and data-interpretation are discussed in detail and an essential sampling checklist is provided. The full range of cosmogenic isotopes is covered and a wide spectrum of in-situ applications are described and illustrated with specific and generic examples of exposure dating, burial dating, erosion and uplift rates and process model verification. Graduate students and experienced practitioners will find this book a vital source of information on the background concepts and practical applications in geomorphology, geography, soil-science, and geology.
Earth as an Evolving Planetary System is based on Kent Condie's classic text, Plate Tectonics and Crustal Evolution, which has been revamped and renamed in order to reflect a new emphasis on the ...evolving interactions of the Earth's systems. This revised volume synthesizes data from the fields of geophysics, oceanography, planetology, and geochemistry. It features new chapters on the Earth's core, biotic systems, and the supercontinent cycle and mantle plume events. It contains expanded treatment of the evolution of the Earth's crust and mantle, carbon cycle, oxygenation of the atmosphere, and the significance of sulfur isotope fractionation. It also includes new information on mass extinctions and catastrophic events over the last four billion years that have transformed the atmosphere, oceans, and life on Earth. By integrating results from many different disciplines, this important text gives students a broader perspective of the Earth Sciences and shows how specialized data contribute to Earth and planetary history. This text is designed for advanced undergraduate and graduate students in Earth, Atmospheric, and Planetary Sciences; and scientists in other disciplines who want to look at the Earth with a broader perspective. * New insight on interaction and evolution of Earth system * Examines the role of castrophic events in Earth's history * New section on the evolution of the mantle
We present an application of deep generative models in the context of partial differential equation constrained inverse problems. We combine a generative adversarial network representing an a priori ...model that generates geological heterogeneities and their petrophysical properties, with the numerical solution of the partial-differential equation governing the propagation of acoustic waves within the earth’s interior. We perform Bayesian inversion using an approximate Metropolis-adjusted Langevin algorithm to sample from the posterior distribution of earth models given seismic observations. Gradients with respect to the model parameters governing the forward problem are obtained by solving the adjoint of the acoustic wave equation. Gradients of the mismatch with respect to the latent variables are obtained by leveraging the differentiable nature of the deep neural network used to represent the generative model. We show that approximate Metropolis-adjusted Langevin sampling allows an efficient Bayesian inversion of model parameters obtained from a prior represented by a deep generative model, obtaining a diverse set of realizations that reflect the observed seismic response.
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