Download or read book Tectonics of the East Pacific Rise 50 to 120S written by David Kenerson Rea and published by . This book was released on 1975 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tectonics of the East Pacific Rise written by Sang-Mook Lee and published by . This book was released on 1995 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: The global mid-ocean ridge system is one of the most striking geological features on the surface of the Earth. In this system, the East Pacific Rise (EPR) is the fastest spreading ridge and is thus considered as the most active magmatically among the plate boundaries. In January and February of 1988, an extensive survey by the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution was conducted along the EPR between 9°05' and 9°55'N to study the crustal structure of the axial region. This thesis, the result of that cruise, comprises four main topics: (1) characterization of normal faulting from Sea Beam bathymetric data, (2) application of mechanical models to explore the hypothesis that buoyancy arising from crustal magma chambers and gravitational spreading of the upper crust are the principal processes leading to the initiation and development of normal faults, (3) investigation of seafloor magnetization anomalies to constrain upper crustal structure, and (4) analysis of gravity anomalies to examine possible correlations between observed variations in seafloor manifestations of volcanism and deformation and underlying structure. Thus, each topic focuses on different levels of the mid-ocean ridge. Together with the results of seismic and other observations, the findings are woven into a better understanding of the tectonic processes and structure of fastspreading mid-ocean ridges.
Download or read book Near bottom Studies of the East Pacific Rise Crest and Tectonics of the Mouth of the Gulf of California written by Roger Lee Larson and published by . This book was released on 1970 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bathymetric and magnetic measurements have been used to delineate the boundary between the North American and Pacific Plates in the vicinity of the mouth of the Gulf of California and indicate a spreading rate of 6 cm/yr. Magnetic anomalies, fracture zones and earthquake mechanisms indicate the validity of the rigid plate assumption for the interactions between the Pacific, American and Cocos plates. A survey with a near-bottom instrument over the East Pacific Rise crest shows lineated abyssal hills with no sediment cover at the rise crest itself. Magnetic field measurements made near the ocean floor show to a certain extent the history of the earth's magnetic field over the last 1.2 million years and show a reversal transition time of 1000 years and intensity fluctuations with periods ranging between 18000 and 50000 years. (Author).
Download or read book Tectonics of the East Pacific Rise 5 to 12 S written by David Kenerson Rea and published by . This book was released on 1974 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: The portion of the East Pacific Rise (EPR) between 5° and 12°S can be subdivided into three areas by fracture zones that offset the rise axis at about 6.5°S and 9°S. In all three regions, the spreading axis of the EPR is defined by a topographic block 300 to 350 m high and about 15 km wide. The axial block commonly has subordinate peaks or shoulders on each flank that vary up to 5 km wide. Analysis of linear magnetic anomalies in the southern of the three areas suggests that sea-floor spreading has been occurring at rates of 80 mm/y to the west and 77 mm/y to the east during the last 1.7 million years (my). The rise axis is offset in two places about 10 km. These displacements are interpreted to be the result of discrete jumps of the site of spreading activity. Reconnaissance data from the east flank of the EPR indicate that spreading activity on this portion of the rise began just over 8 my ago when the site of crustal accretion jumped westward from the now dormant Galapagos Rise. About 4.6 my ago the section of rise crest between approximately 10.5°S and the 9°S fracture zone jumped westward a distance of at least 10 km, isolating the pre-existing axial block. By 1.7 my ago, this axial offset no longer existed, implying a relatively westward migration of the rise axis south of 10.5° during the period from 4.6 to 1.7 my ago. The two offsets of the present axis occurred between 1.6 and 0.9 my ago and 0.7 my ago and the present in the north and south, respectively. The formation of the axial block, its associated shoulders and the abyssal topography, apparently consisting of tilted fault blocks with steep sides facing the axis, can be explained by an empirical model. This model combines extrusion of basalt along the spreading axis to form the axial block and rotational faulting to form the shoulders of the block and then lower the shoulders to merge with the abyssal topography of the uppermost rise flanks. In the region north of the 6.5°S fracture zone, seismic activity on the rise crest, combined with topographic information, suggests that the EPR axis is unstable here and that it is in the process of reorienting to a more stable regional trend. Identification and mapping of magnetic anomalies in the vicinity of 6°S reveal a spreading rate of about 77 mm/y, an episode of oblique spreading that occurred 1.7 my ago, and a 10 km westward jump of the axis which occurred since 0.7 my ago. The fracture zone at 6.5°S offsets the EPR axis 55 km right laterally. Both the bathymetric and magnetic expression of this fracture zone are markedly reduced a few tens of kilometers away from its active portion, implying that some change in the processes forming the fracture zone occurred about 0.3 my ago. Between the fracture zones at 6.5° and 9°S, two deactivated segments of the rise axis, each about 40 km long, occur 90 and 65 km west of the currently active axis. These inactive axial segments were isolated by eastward jumps of the spreading center. The more northerly jump, along 6.5°S, occurred 0.3 my ago and spanned 68 km. The other, along 7°S, covered a similar distance and is either just completed or still going on. Reconnaissance data from this part of the EPR suggests that sea-floor spreading began here about 6.5 my ago and has been continuing at a rate of approximately 78 mm/y.
Download or read book East Pacific Rise at 21 N written by Robert D. Ballard and published by . This book was released on 1981 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physical Geology written by Steven Earle and published by . This book was released on 2016-08-12 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a discount Black and white version. Some images may be unclear, please see BCCampus website for the digital version.This book was born out of a 2014 meeting of earth science educators representing most of the universities and colleges in British Columbia, and nurtured by a widely shared frustration that many students are not thriving in courses because textbooks have become too expensive for them to buy. But the real inspiration comes from a fascination for the spectacular geology of western Canada and the many decades that the author spent exploring this region along with colleagues, students, family, and friends. My goal has been to provide an accessible and comprehensive guide to the important topics of geology, richly illustrated with examples from western Canada. Although this text is intended to complement a typical first-year course in physical geology, its contents could be applied to numerous other related courses.
Download or read book Tectonics and Plate Boundary Processes Along the Southeast Indian Ridge and the East Pacific Rise written by James Andrew Conder and published by . This book was released on 2001 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Tectonic Plates are Moving written by Roy Livermore and published by Oxford University Press. This book was released on 2018-03-23 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plate tectonics is a revolutionary theory on a par with modern genetics. Yet, apart from the frequent use of clichés such as 'tectonic shift' by economists, journalists, and politicians, the science itself is rarely mentioned and poorly understood. This book explains modern plate tectonics in a non-technical manner, showing not only how it accounts for phenomena such as great earthquakes, tsunamis, and volcanic eruptions, but also how it controls conditions at the Earth's surface, including global geography and climate. The book presents the advances that have been made since the establishment of plate tectonics in the 1960s, highlighting, on the 50th anniversary of the theory, the contributions of a small number of scientists who have never been widely recognized for their discoveries. Beginning with the publication of a short article in Nature by Vine and Matthews, the book traces the development of plate tectonics through two generations of the theory. First generation plate tectonics covers the exciting scientific revolution of the 1960s and 1970s, its heroes and its villains. The second generation includes the rapid expansions in sonar, satellite, and seismic technologies during the 1980s and 1990s that provided a truly global view of the plates and their motions, and an appreciation of the role of the plates within the Earth 'system'. The final chapter bring us to the cutting edge of the science, and the latest results from studies using technologies such as seismic tomography and high-pressure mineral physics to probe the deep interior. Ultimately, the book leads to the startling conclusion that, without plate tectonics, the Earth would be as lifeless as Venus.
Download or read book This Dynamic Earth written by W. Jacquelyne Kious and published by DIANE Publishing. This book was released on 1996 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents the online edition of the publication "This Dynamic Earth: The Story of Plate Tectonics" (ISBN 0-16-048220-8) by W. Jacquelyne Kious and Robert I. Tilling, published by the U.S. Geological Survey (USGS) in Denver, Colorado. Posts contact information via mailing address, telephone and fax numbers, and e-mail. Notes that a hard copy of the publication is available. Provides a table of contents and endnotes. Links to the USGS home page.
Download or read book Tectonics of Mid ocean Ridges written by John Dee Rogers Bicknell and published by . This book was released on 1986 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book This Dynamic Earth written by W. Jacquelyne Kious and published by Geological Survey (USGS). This book was released on 1996 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early 1960s, the emergence of the theory of plate tectonics started a revolution in the earth sciences. Since then, scientists have verified and refined this theory, and now have a much better understanding of how our planet has been shaped by plate-tectonic processes. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and present. Indeed, the notion that the entire Earth's surface is continually shifting has profoundly changed the way we view our world.
Download or read book Plate Tectonics written by Xavier Le Pichon and published by Elsevier. This book was released on 2013-10-22 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developments in Geotectonics, 6: Plate Tectonics focuses on the exposition of the plate-tectonics hypothesis, as well as plate boundaries, stratification, and kinematics. The book first offers information on the rheological stratification of the mantle and kinematics of relative movements. Topics include lithosphere, asthenosphere, kinematics of finite motions, measurements of instantaneous movements, and worldwide kinematic pattern. The text then ponders on movements relative to a frame external to the plates and processes at accreting plate boundaries. Discussions focus on reference frames, paleomagnetic synthesis, creation of oceanic crust, and continental rifts. The publication elaborates on processes at consuming plate boundaries, including sinking plate model, structure of trenches and associated island arcs and cordilleras, and consumption of continent-bearing lithosphere. The text is a valuable source of data for readers interested in plate tectonics.
Download or read book The Ocean of Truth written by Henry William Menard and published by Princeton University Press. This book was released on 2014-07-14 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: Menard begins with the leading hypotheses (such as that the earth expands) and the supporting evidence for each. He traces the crucial work of the 1960s year by year as researchers debated hypotheses in correspondence and at frequent meetings. Throughout the book Professor Menard considers the implications of his story for the sociology of science and the goals of scientific research. Originally published in 1986. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover 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.
Download or read book Surge Tectonics A New Hypothesis of Global Geodynamics written by Arthur A. Meyerhoff and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: TECTONlCS AND PHYSICS Geology, although rooted in the laws of physics, rarely has been taught in a manner designed to stress the relations between the laws and theorems of physics and the postulates of geology. The same is true of geophysics, whose specialties (seismology, gravimetIy, magnetics, magnetotellurics) deal only with the laws that govern them, and not with those that govern geology's postulates. The branch of geology and geophysics called tectonophysics is not a formalized discipline or subdiscipline, and, therefore, has no formal laws or theorems of its own. Although many recent books claim to be textbooks in tectonophysics, they are not; they are books designed to explain one hypothesis, just as the present book is designed to explain one hypothesis. The textbook that comes closest to being a textbook of tectonophysics is Peter 1. Wyllie's (1971) book, The Dynamic Earth. Teachers, students, and practitioners of geology since the very beginning of earth science teaching have avoided the development of a rigorous (but not rigid) scientific approach to tectonics, largely because we earth scientists have not fully understood the origin of the features with which we are dealing. This fact is not at all surprising when one considers that the database for hypotheses and theories of tectonics, particularly before 1960, has been limited to a small part of the exposed land area on the Earth's surface.
Download or read book Plate Tectonics written by American Geophysical Union and published by . This book was released on 1980 with total page 1040 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Continental Drift Controversy Volume 4 Evolution into Plate Tectonics written by Henry R. Frankel and published by Cambridge University Press. This book was released on 2012-04-26 with total page 697 pages. Available in PDF, EPUB and Kindle. Book excerpt: The resolution of the sixty-year debate over continental drift, culminating in the triumph of plate tectonics, changed the very fabric of Earth science. This four-volume treatise on the continental drift controversy is the first complete history of the origin, debate and gradual acceptance of this revolutionary theory. Based on extensive interviews, archival papers and original works, Frankel weaves together the lives and work of the scientists involved, producing an accessible narrative for scientists and non-scientists alike. This fourth volume explains the discoveries in the mid 1960s which led to the rapid acceptance of seafloor spreading theory and how the birth of plate tectonics followed soon after with the geometrification of geology. Although plate tectonics did not explain the cause or dynamic mechanism of drifting continents, it provided a convincing kinematic explanation that continues to inspire geodynamic research to the present day.
Download or read book This Dynamic Earth written by W. Jacquelyne Kious and published by Geological Survey (USGS). This book was released on 1996 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early 1960s, the emergence of the theory of plate tectonics started a revolution in the earth sciences. Since then, scientists have verified and refined this theory, and now have a much better understanding of how our planet has been shaped by plate-tectonic processes. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and present. Indeed, the notion that the entire Earth's surface is continually shifting has profoundly changed the way we view our world.
