Download or read book A GEOPHYSICAL ANALYSIS OF THE OROZCO FRACTURE ZONE AND THE TECTONIC EVOLUTION OF THE NORTHERN COCOS PLATE written by and published by . This book was released on 1975 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: In April of 1974, Oregon State University conducted a geophysical survey of the Orozco fracture zone, a Left-lateral transform fault which offsets the East Pacific Rise off the coast of Mexico near 15°N, 105°W. Magnetic, gravity, bathymetric, and seismic reflection data were collected during a four day period. This survey is combined with previous surveys by Oregon State University and other institutions to provide a geophysical interpretation of the Orozco fracture zone and the surrounding area and to develop a tectonic history of the northern Cocos plate. The Orozco fracture zone is characterized by a typical zone of seismicity and an offset in the magnetic anomaly pattern. There is, however, a conspicuous absence of a well defined topographic trough. This appears to be a result of the small age offset of the ridge crest, a reorientation of the fracture zone trend, and a possible southward migration of the fracture zone down the ridge axis. Three crustal and subcrustal cross sections over the Orozco fracture zone are constructed from the gravity data. One, across the active portion between the ridge offset, shows the active troughs to be underlain by a broad, low-density root extending two kilometers into the mantle. Two gravity cross sections across the East Pacific Rise show a thinning of oceanic layer 3 of nearly 2 kilometers at the rise crest and a corresponding 0.5 kilometer thickening of layer 2. A large magnetic anomaly of over 1300 gammas is found at the intersection of the Orozco fracture zone and the East Pacific Rise. A comparison with a very similar observation at the intersection of the Juan de Fuca ridge and the Blanco fracture zone in the northeast Pacific suggests that the East Pacific Rise is "leaking" into the fracture zone in this area. Many features have been observed on the northern Cocos plate which cannot be accounted for by present Pacific-Cocos motion the northeast strike of the eastern extension of the Orozco fracture zone, an apparent fanning of magnetic anomalies, and the northeast strike, as well as the origin, of the Tehuantepec ridge. Several possible schemes are examined to explain these observations and all but one are completely eliminated. The proposed explanation supposes a reorientation of the spreading center after a large change in the Pacific- Cocos pole of rotation resulting in the Zed pattern described by Menard and Atwater (1968).
Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2013-11-21 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and dis seminated by the Center for lnformation and Numerica/ Data Analysis and Synthesis (C/NDAS) * at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the ac tivity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficia! to the academic and general scientific and technical community. After fi ve years of this joint undertaking we had concluded that it was in the interest of ali concerned if the printing and distribution of the volume were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and App/ied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. Ali back issues can also be ordered from Plenum. We have reported in Volume 21 (thesis year 1976) a total of 10,586 theses titles from 25 Canadian and 219 United States universities. We are sure that this broader base for theses titles reported will greatly enhance the value of this important annual reference work.
Download or read book The Bathymetry and Magnetics of the Wilkes Fracture Zone of the East Pacific Rise at 90S written by Charles L. Kureth and published by . This book was released on 1980 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Marine Gravity written by P. Dehlinger and published by Elsevier. This book was released on 1978-01-01 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine Gravity
Download or read book O S U Theses and Dissertations 1970 1977 written by Oregon State University and published by . This book was released on 1980 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cocos Plate Structure Along the Middle America Subduction Zone Off Oaxaca and Guerrero Mexico written by Nancy Marie Kanjorski and published by . This book was released on 2003 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cenozoic Tectonics and Volcanism of Mexico written by Hugo Delgado-Granados and published by Geological Society of America. This book was released on 2000 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reference written by and published by . This book was released on 1977 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cenozoic History and Paleoceanography of the Central Equatorial Pacific Ocean written by Tjeerd Hendrik Van Andel and published by Geological Society of America. This book was released on 1975 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanic Abstracts with Indexes written by and published by . This book was released on with total page 976 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography and Index of Geology written by and published by . This book was released on 1992 with total page 1404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Southern and Central Mexico Basement Framework Tectonic Evolution and Provenance of Mesozoic Cenozoic Basins written by Uwe C. Martens and published by Geological Society of America. This book was released on 2021-12-23 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geology and Tectonics of Northwestern South America written by Fabio Cediel and published by Springer. This book was released on 2018-08-10 with total page 1001 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of the geological evolution of the Northern Andes and contiguous shield areas, with a focus upon Colombia. Updated geological interpretations are supported by modern lithogeochemical, seismic, gravity and magnetic data and radiogenic isotope and radiometric age determinations. The composite data permits a detailed interpretation of the tectono-magmatic history of the Northern Andean Block, including the Andes of Colombia, northern Ecuador, western Venezuela and eastern Panamá. Tectonic reconstructions based upon characterization of more than thirty litho-tectonic and morpho-structural units, terrane assemblages and tectonic realms, and their bounding suture and fault systems, highlight the intimate and complementary Mesozoic-Cenozoic history of the Northern Andean Block and the Pacific and Caribbean Plates. The complex nature of Northern Andean assembly contrasts with ‘‘classical’’ Central Andean ‘‘Cordilleran-type’’ orogenic models. Differences render the application of typical Cordilleran-type models inappropriate for the Colombian Andes. The importance of underlying Proterozoic through mid-Mesozoic elements, in the development of Meso-Cenozoic Northern Andean orogeny-phase tectonic configurations is analyzed in the light of spatial-temporal studies and reconstructions related to basin formation, sedimentation, deformation, uplift mechanisms, structural style and magmatic evolution. The pre-Andean architecture of north western South America has played a pre-determinative role in the development of the Northern Andean orogenic system. 16 contributions analyze key stratigraphic, structural, metamorphic, magmatic and tectonic questions, and provide solutions as far as the most recent published field-based studies permit. The volume provides geological interpretations and tectonic models which contrast with repetitive theoretical proposals frequently found in the available literature.
Download or read book Mechanics Problems in Geodynamics Part II written by Ren Wang and published by Springer Science & Business Media. This book was released on 1996-05 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reprint from Pure and Applied Geophysics (PAGEOPH), Volume 146 (1996), No. 3/4
Download or read book The Eastern Pacific Ocean and Hawaii written by Edward L. Winterer and published by . This book was released on 1989 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: Book with articles by various authors on the geology of the northeastern part of the Pacific ocean and the adjacent parts of the North American continental margin. One chapter covers the Hawaiian-Emperor volcanic chain.
Download or read book Current Programs written by and published by . This book was released on 1975 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fourth International Gondwana Symposium written by and published by . This book was released on 1979 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:
