Download or read book Subduction Zone to mantle Fluxes of Trace Elements at Intraoceanic Margins and Implications for Mantle Evolution written by Katherine Anne Porter and published by . This book was released on 2005 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Intra oceanic Subduction Systems written by Robert D. Larter and published by Geological Society of London. This book was released on 2003 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recycling of oceanic plate back into the Earth's interior at subduction zones is one of the key processes in Earth evolution. Volcanic arcs, which form above subduction zones, are the most visible manifestations of plate tectonics, the convection mechanism by which the Earth loses excess heat. They are probably also the main location where new continental crust is formed, the so-called 'subduction factory' About 400f modern subduction zones on Earth are intra-oceanic. These subduction systems are generally simpler than those at continental margins as they commonly have a shorter history of subduction and their magmas are not contaminated by ancient sialic crust. They are therefore the optimum locations for studies of mantle processes and magmatic addition to the crust in subduction zones.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2006 with total page 848 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Long term Evolution of Subduction Zones written by Dagmar Olbertz and published by Faculteit Aardwetenschappen Universiteit Utrecht. This book was released on 1997 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution of Oceanic Margins written by Nathaniel Clark Miller and published by . This book was released on 2013 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis investigates three processes that control the evolution of oceanic margins. Chapter 2 presents seismic images of a ~2-km-thick evaporite body in Guaymas Basin, central Gulf of California. In rifts, evaporites form under conditions unique to the latest stages of continental rupture, and the presence, age, thickness, and shape place new constraints on the history of early rifting there. Chapter 3 presents numerical experiments that show that diapirs can form in sediments on the down-going plate in subduction zones and rise into the mantle wedge, delivering the sedimentary component widely observed in arc magmas. Chapter 4 presents measurements of seismic anisotropy from wide-angle, active-source data from the Middle America Trench that address the hypothesis that the upper mantle is hydrated by seawater flowing along outer-rise normal faults. These measurements indicate that the upper mantle is ~1.57 to 6.89% anisotropic, and this anisotropy can be attributed to bending-related faulting and an inherited mantle fabric. Accounting for anisotropy reduces previous estimates for the amount of water stored in the upper mantle of the down-going plate from ~2.5 to 1.5 wt%, a significant change in subduction zone water budgets.
Download or read book The Crust written by R.L. Rudnick and published by Elsevier. This book was released on 2005-12-19 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Treatise on Geochemistry is the first work providing a comprehensive, integrated summary of the present state of geochemistry. It deals with all the major subjects in the field, ranging from the chemistry of the solar system to environmental geochemistry. The Treatise on Geochemistry has drawn on the expertise of outstanding scientists throughout the world, creating the reference work in geochemistry for the next decade. Each volume consists of fifteen to twenty-five chapters written by recognized authorities in their fields, and chosen by the Volume Editors in consultation with the Executive Editors. Particular emphasis has been placed on integrating the subject matter of the individual chapters and volumes. Elsevier also offers the Treatise on Geochemistry in electronic format via the online platform ScienceDirect, the most comprehensive database of academic research on the Internet today, enhanced by a suite of sophisticated linking, searching and retrieval tools.
Download or read book Inside the Subduction Factory written by John Eiler and published by American Geophysical Union. This book was released on 2003 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 138. Subduction zones helped nucleate and grow the continents, they fertilize and lubricate the earth's interior, they are the site of most subaerial volcanism and many major earthquakes, and they yield a large fraction of the earth's precious metals. They are obvious targets for study—almost anything you learn is likely to impact important problems—yet arriving at a general understanding is notoriously difficult: Each subduction zone is distinct, differing in some important aspect from other subduction zones; fundamental aspects of their mechanics and igneous processes differ from those in other, relatively well-understood parts of the earth; and there are few direct samples of some of their most important metamorphic and metasomatic processes. As a result, even first-order features of subduction zones have generated conflict and apparent paradox. A central question about convergent margins, for instance—how vigorous magmatism can occur where plates sink and the mantle cools—has a host of mutually inconsistent answers: Early suggestions that magmatism resulted from melting subducted crust have been emphatically disproved and recently just as emphatically revived; the idea that melting is fluxed by fluid released from subducted crust is widely held but cannot explain the temperatures and volatile contents of many arc magmas; generations of kinematic and dynamic models have told us the mantle sinks at convergent margins, yet strong evidence suggests that melting there is often driven by upwelling. In contrast, our understanding ofwhy volcanoes appear at ocean ridges and "hotspots"—although still presenting their own chestnuts—are fundamentally solved problems.
Download or read book When Did Plate Tectonics Begin on Planet Earth written by Kent C. Condie and published by Geological Society of America. This book was released on 2008-01-01 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Inspired by a GSA Penrose Conference held in Lander, Wyoming, June 14-18, 2006, this volume discusses the beginning and evolution of plate tectonics on Earth, and gives readers an introduction to some of the uncertainties and controversies related to the evolution of the planet. In the first three sections of the book, which cover isotopic, geochemical, metamorphic, mineralization, and mantle geodynamic constraints, a variety of papers address the question of when "modern-style" plate tectonics began on planet Earth. The next set of papers focuses on the geodynamic or geophysical constraints for the beginning of plate tectonics. The volume's final section synthesizes a broad range of evidence, from planetary analogues and geodynamic modeling, to Earth's preserved geologic record. This work provides an excellent graduate level text summarizing the current state of knowledge and will be of interest to a wide range of earth and planetary scientists."--Publisher's website.
Download or read book Arc Continent Collision written by Dennis Brown and published by Springer Science & Business Media. This book was released on 2011-06-29 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arc-continent collision has been one of the important tectonic processes in the formation of mountain belts throughout geological time, and it continues to be so today along tectonically active plate boundaries such as those in the SW Pacific or the Caribbean. Arc-continent collision is thought to have been one of the most important process involved in the growth of the continental crust over geological time, and may also play an important role in its recycling back into the mantle via subduction. Understanding the geological processes that take place during arc-continent collision is therefore of importance for our understanding of how collisional orogens evolve and how the continental crust grows or is destroyed. Furthermore, zones of arc-continent collision are producers of much of the worlds primary economic wealth in the form of minerals, so understanding the processes that take place during these tectonic events is of importance in modeling how this mineral wealth is formed and preserved. This book brings together seventeen papers that are dedicated to the investigation of the tectonic processes that take place during arc-continent collision. It is divided into four sections that deal firstly with the main players involved in any arc-continent collision; the continental margin, the subduction zone, and finally the volcanic arc and its mineral deposits. The second section presents eight examples of arc-continent collisions that range from being currently active through to Palaeoproterozoic in age. The third section contains two papers, one that deals with the obduction of large-slab ophiolites and a second that presents a wide range of physical models of arc-continent collision. The fourth section brings everything that comes before together into a discussion of the processes of arc-continent collision.
Download or read book Subduction Zone Magmatism written by Yashiyuki Tatsumi and published by Wiley. This book was released on 1995-06-15 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Subduction zones are major sites of volcanism on the Earth. As one crustal plate sinks or is pushed beneath another, hot magma is produced and the resultant magma flux is fundamental to both the thermal evolution and chemical differentiation of the mantle and the Earth itself. To understand these evolutionary processes, we need to understand the physical and chemical consequences of all aspects of the subduction process. In this book, the authors present a simple, current and comprehensive model that explains the dominant geological processes at work in subduction zones. Structuring the book around the model, the authors describe the physical characteristics and geochemical dynamics of subduction zones, arc magma generation, and the dynamics and flow in the mantle. Students and researchers alike will find this book of immense value in understanding this most complex of subjects.
Download or read book Mantle Convection in the Earth and Planets written by Gerald Schubert and published by Cambridge University Press. This book was released on 2001 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive and up-to-date synthesis of all aspects of mantle convection, for advanced students and researchers.
Download or read book Evolution and Inheritance of Cascadia Sub arc Mantle Reservoirs written by Sarah Ashley Bromley and published by . This book was released on 2011 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inheritance from pre-existing mantle domains and fluid and melt contributions from active subduction together produce the geochemical signatures of mantle-derived arc basalts. In this context, this work evaluates the evolution of Cascadia mantle sources by documenting the isotopic and compositional characteristics of primitive basalts along a transect across the Eocene-Oligocene Proto-Cascadia (EOPC) arc at ~44.5-45.5° N. Primitive EOPC flows, dikes, and sills are exposed across a ~300 km transect that includes the Oregon Coast Range in the Cascadia forearc, the Western Cascades, flanking the modern arc, and the John Day and Eastern Clarno formations east of the Cascades. Like the modern arc, EOPC was built upon accreted terranes of western North America and within the Columbia embayment, which is lithosphere of oceanic affinity that crops out as the Siletzia terrane in the forearc and extends beneath the arc to the backarc. Potential mantle source reservoirs for EOPC magmas include contributions from mantle domains related to pre-existing underlying terranes, distinct North America lithosphere, and depleted Pacific-like upper mantle. In addition, the geochemical characteristics of EOPC magmas have likely been overprinted by subduction processes. Major, trace element, and isotopic data from the EOPC reveal a heterogeneous mantle source that was variably influenced by subduction processes. In the forearc, the high field strength (HFSE) enriched basalts of the Oregon Coast Range represent low degree partial melts of a relatively enriched mantle source. Despite this enriched character, there is little evidence in the trace element or isotopic data to suggest that the OCR (Oregon Coast Range) samples have been strongly influenced by either a crustal or subduction component. Their distinctive 206Pb/204Pb enrichment (as compared to 207Pb/204Pb) distinguishes the forearc magmas from the arc and backarc magmas and also from a hypothetical Cascadia subduction component. Forearc EOPC magmas share a mantle source with the accreted Siletzia terrane, as evidenced by their shared 206Pb/204Pb enrichment. At the apparent arc axis, the Western Cascades produced a diversity of primitive magmas that are, for the most part, interpreted to result from higher degrees of partial melting of a less enriched source. Fluid fluxing appears to have facilitated mantle melting beneath the Western Cascades. Additionally, the mantle beneath the arc may be slightly influenced by the 206Pb/204Pb enriched source underlying the forearc. Though this effect is difficult to resolve, the Western Cascades samples appear to be slightly more variable in 206Pb/204Pb (and generally higher in 206Pb/204Pb at a given 207Pb/204Pb) than their backarc counterparts, suggesting such an influence. Both trace element and isotopic data suggest a significant subduction contribution to EOPC backarc primitive magmas. The EOPC backarc magmas appear to have originated from a heterogeneous mantle and are variably influenced by a subduction component. Though this subduction influence could be an inherited feature, the affinity between John Day and Eastern Clarno magmas and a modern Cascadia sediment source suggest that this is at least a relatively young feature. Taken together, these results demonstrate the heterogeneity of source and process across the Eocene-Oligocene arc. Apparent subduction contribution increases from the geographic forearc to backarc, perhaps indicating a wider arc than is typically envisioned at the time. The distinct 206Pb/204Pb enrichment associated with the Siletzia mantle and apparent in the forearc appears to wane in influence to the east, having at most a minor influence on the Western Cascade arc magmas. As with the Siletzia mantle domain in EOPC arc and backarc, mantle domains associated with the Western Cascades and John Day/Eastern Clarno magmas do not persist in the High Cascades or High Lava Plains. Beneath and behind the arc, mantle reservoirs appear to have been largely replaced since the Eocene-Oligocene. However, the High Lava Plains basalts appear to carry a paleo-enrichment signature that may be an inherited feature from advected mantle. If this enriched mantle was advected from beneath North America, it may explain the observation that High Lava Plains basalts are more enriched to the east.
Download or read book The Upper Mantle written by A. R. Ritsema and published by Elsevier. This book was released on 2013-10-22 with total page 657 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developments in Geotectonics, 4: The Upper Mantle focuses on the upper mantle and its influence on the development of the earth's crust, including history of the moon and other planets and volcanology. The selection first offers information on the origin of the earth, including ideas on the formation process of the terrestrial planets, condensation of dust particles, nature of the earth's core, thermal history of the earth, and fractionation of iron in the terrestrial planets. The text then ponders on the beginning of continental evolution, as well as the oldest rocks of the earth's crust, thermal history of the moon, and early history of the other planets. The text elaborates on magmatic activity as the major process in the chemical evolution of the earth's crust and mantle; trends in the evolution of continents; progress and problems in volcanology; and pressure and temperature conditions and tectonic significance of regional and ocean-floor metamorphism. The manuscript also takes a look at the state of mantle minerals, melting temperatures in the earth's mantle, and geomagnetic induction studies and the electrical state of the upper mantle. The publication is a dependable reference for readers interested in the study of the upper mantle.
Download or read book Orogenic Andesites and Crustal Growth written by A. Gómez-Tuena and published by Geological Society of London. This book was released on 2014-01-24 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orogenic andesites have long intrigued scientists because of their remarkable compositional similarities to the continental crust. The significance of orogenic andesites as proxies to continental crust formation has been recognized for over 30 years, but no consensus model of andesite genesis exists. Much of the controversy revolves around whether orogenic andesites are primary mantle melts of slab and mantle materials, or instead evolve from basaltic mantle melts at shallower crustal levels. In three sections, this book provides an overview of andesite genesis at convergent margins that focuses on the slab–mantle interaction, crustal processing and andesite evolution through the life of volcanic arcs. Without favouring a particular view, the books aims to engender cross-fertilization and discussion that will smooth the pathway towards a holistic communal model of andesite petrogenesis and its role within the broader geochemical cycles of the Earth.
Download or read book Continental Mantle written by Martin A. Menzies and published by Oxford University Press, USA. This book was released on 1990 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Very Good,No Highlights or Markup,all pages are intact.
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2566 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Special Papers written by and published by . This book was released on 1934 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt:
