Download or read book Fluid Flow and Deformation at an Active Continental Margin written by Janet Wai Ngan Yun and published by . This book was released on 2000 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Margins written by National Research Council and published by National Academies Press. This book was released on 1990-02-01 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately 70 percent of the world's population is concentrated in the coastal borderlands, which geologists recognize to be the present continental margins. This new book on these continental margins provides a detailed account of a meeting which brought together specialists in marine and terrestrial geology, geochemistry, and geophysics. The workshop garnered widespread support and enthusiasm for a new direction in margins research focused on interdisciplinary studies of the fundamental processes of continental margin evolution. Scientific problems and solutions were identified for both divergent and convergent margins. Results of the workshop show that many of the fundamental plate interaction processes are common to all margins, whether formed by extension, contraction, or translation. This conclusion suggests a unified approach to margins research. A margins initiative has been proposed to follow up on the workshop results by developing science programs aimed at understanding the processes that control the initiation and evolution of continental margins.
Download or read book The Dynamics of Fluid Flow and Associated Chemical Fluxes at Active Continental Margins written by Evan Alan Solomon and published by . This book was released on 2007 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Active fluid flow plays an important role in the geochemical, thermal, and physical evolution of the Earth's crust. This dissertation investigates the active fluid flow and associated chemical fluxes at two dynamic continental margins: The Costa Rica subduction zone and the northern Gulf of Mexico hydrocarbon province, using novel seafloor instrumentation for continuous monitoring of fluid flow rates and chemistry. Traditional pore fluid sampling methods and flow rate models only provide a steady-state view of these types of hydrogeochemical systems. The data presented in this thesis, however, show that these systems are dynamic with short period transients in both flow rates and chemistry having a wide range of implications. Osmotically pumped fluid samplers and a new borehole fluid flow meter were deployed in CORKed borehole observatories installed in two active hydrogeochemical systems at the Costa Rica subduction zone. The data collected by this effort provide critical information on the average and transient hydrogeochemical state of the upper igneous basement and subduction thrust. The results suggest that the upper igneous basement provides an efficient pathway for fluids expelled from the forearc that should be included in models of subduction zone hydrogeology and deformation. Two transients in flow rates along the décollement are the result of aseismic slip dislocations that ruptured through the seismogenic zone. These observations provide insight into the dynamics of episodic strain and the associated fluid flow along the décollement, and may provide an analog for the strain and flow response prior to and during a large subduction zone earthquake. Recent studies have shown that when the subduction flux of incompatible elements, such as Ba, in the incoming sediment section is high, the arc volcanoes erupt lavas enriched in these elements. Mass balance calculations based on the sedimentary input flux of Ba at reference sections drilled seaward of the trench and the enrichment of Ba in volcanic arcs, suggest 20-30% of the subducted sediment Ba budget is recycled to the arc. A detailed analysis of pore fluid and sediment Ba concentrations from Ocean Drilling Program (ODP) cores collected at the Costa Rica subduction zone, shows that barite dissolution in the forearc can have a profound impact on the amount of Ba recycled to the arc volcanoes and mantle. At the Costa Rica margin, approximately 60% of the incoming sedimentary Ba is lost in the shallow subduction zone, greatly reducing previous estimates of the Ba input flux to the depths of magma generation based solely on the reference section seaward of the trench. These results suggest that current estimates of the global sediment Ba contribution to volcanic arcs should be reevaluated, and may need to be revised upwards. Four newly designed fluid flow meters/chemical samplers, called the MOSQUITO, were deployed for 430 days at a seafloor gas hydrate outcrop in the northern Gulf of Mexico to determine how dynamic subsurface fluid flow influences gas hydrate stability and to quantify the associated methane fluxes into the ocean and atmosphere. The results show that gas hydrate continuously formed within the sediments despite a highly transient fluid flow field and variable bottom water temperatures. A model is proposed where gas hydrate formation occurred as a result of long-term emanation of CH4 at focused gas vents followed by a more diffuse intergranular methane flux. From the long-term flow rate record, the estimated CH4 flux across the seafloor to the water column from focused vents at the Bush Hill seep is ~5.106 mol/yr. The surface water CH4 concentrations above the perennial hydrocarbon plumes emitted at these high-flux gas seeps are up to 2,000 times supersaturated. The estimated diffusive CH4 fluxes to the atmosphere from individual plumes are 3-4 orders of magnitude greater than previously reported from the deepwater marine environment. Extrapolation over the Gulf of Mexico continental shelf and slope indicates that these perennial hydrocarbon plumes emit at least 0.1 to 2.3 Tg CH4 yr−−1, and suggests submarine hydrocarbon seeps in the Gulf of Mexico and in other oil-rich regions are globally significant sources of 14C-dead ("fossil") methane to the atmosphere.
Download or read book Dynamics of Passive Margins written by R. A. Scrutton and published by American Geophysical Union. This book was released on 1982 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Passive Margins written by K.R. McClay and published by Geological Society of London. This book was released on 2020-07-01 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume has evolved from papers written in memory of Professor David Roberts. They summarize the key findings of recent research on passive margins, from tectonics, bathymetry, stratigraphy and sedimentation, structural evolution and magmatism. Papers include analyses of the central and southern Atlantic margins of South America and Africa, papers on magmatism and extension in the NE Brazilian margin and on the Cote de Ivoire margin, rift architectures of the NW Red Sea margin, tectonics of the eastern Mediterranean margin, salt tectonics of passive margins of the Gulf of Mexico and Brazil, and papers on the NW Shelf margin of Australia. The volume provides readers with new insights into the complexities of passive margin systems that are in reality, not so passive.
Download or read book Compressional Deformation and Exhumation in Sedimentary Basins at passive Continental Margins with Implications for Hydrocarbon Exploration and Development written by David Ronald Tassone and published by . This book was released on 2014 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is growing recognition that extensive phases of compressional deformation and exhumation have interrupted the post-rift subsidence histories of some economically important 'passive' continental margins. Understanding the distribution, magnitude, chronology and causes of exhumation and compressional deformation at these margins can reduce exploration uncertainty. The Otway and Faroe-Shetland basins along the southern Australian margin and northwest European Atlantic 'passive' margins, respectively, provide ideal natural laboratories to further understand syn and post-rift compressional deformation, inversion and exhumation. Post-Albian exhumation in the Otway Basin was quantified to be ~400-3600 m across the eastern and northern parts of basin using a new sonic transit time-depth trend, which represents normal compaction of volcaniclastic shales deposited within a fluvio-lacustrine environment - unlike any other such trends previously published. These estimates are consistent with those from complementary thermal, palynological and seismic datasets. Whilst the impacts of exhumation are well known for conventional hydrocarbon systems, this study is amongst the first to highlight the implications of exhumation on unconventional hydrocarbon systems, in particular related to petrographical and geomechanical rock properties. Exhumation in the Otway Basin is mainly related to mid-Cretaceous and Neogene neotectonic compressional deformation and inversion episodes, with the latter strongly governed by the contemporary stress state. Using complementary geophysical datasets and considering lithological heterogeneity, basement fabrics and variations in structural style with depth - factors generally neglected in previous geomechanical-focused studies in this region - it is possible to better understand the relationship between neotectonic deformation and stress. Comparisons between bulk crustal strain rates based on Neogene shortening estimates, and present-day strain rates of based on earthquake data and geological observations demonstrates that strain rates in the Otway Basin have declined since the onset of Neogene compressional deformation and exhumation. Neogene bulk crustal strain rates determined independently from shortening estimates and exhumation magnitudes yield similar results, suggesting that Neogene exhumation in the eastern Otway Basin can be accounted for solely by crustal shortening within a mildly compressional intraplate stress field, with ~30% of the total present-day strain rate accounted for by aseismic deformation. In the central parts of the offshore Otway Basin, where there is very thick preserved Upper Cretaceous sequence and few indications of major post-Albian tectonic activity, significant and previously unreported overpressures are examined. Pore pressure gradients exceed ~16 MPa/km within the fine-grained Upper Cretaceous Belfast and Flaxman formations, and are most likely due to a disequilibrium compaction associated with Pliocene burial by a proto-Murray River discharge. Estimating exhumation in the Otway Basin using sonic log data provided consistent values with thermal-based techniques, indicating that heating can be related (in part) to deeper burial. However, this may not hold true in all basins. More than ~400m of post-Danian exhumation was quantified using sonic data along the Rona High in the Faroe-Shetland region where thermal history data indicates anomalous heating due to transient hot fluid flow and is problematic for exhumation analyses. This exhumation likely occurred during the Oligocene to Mid-Miocene in response to a major reorganisation of the northern North Atlantic spreading system.
Download or read book Geology of the Continental Margins written by Gilbert Boillot and published by Longman Publishing Group. This book was released on 1981 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crustal Heat Flow written by G. R. Beardsmore and published by Cambridge University Press. This book was released on 2001-08-06 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: A handbook for geologists and geophysicists who manipulate thermal data; professionals researchers, and advanced students.
Download or read book In Situ Measurement of Fluid Flow from Cold Seeps at Active Continental Margins written by P. Linke and published by . This book was released on 1993 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Continental Margin Sedimentation written by Charles A. Nittrouer and published by John Wiley & Sons. This book was released on 2009-03-12 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume on continental margin sedimentation brings together an expert editorial and contributor team to create a state-of-the-art resource. Taking a global perspective, the book spans a range of timescales and content, ranging from how oceans transport particles, to how thick rock sequences are formed on continental margins. Summarizes and integrates our understanding of sedimentary processes and strata associated with fluvial dispersal systems on continental shelves and slopes Explores timescales ranging from particle transport at one extreme, to deep burial at the other Insights are presented for margins in general, and with focus on a tectonically active margin (northern California) and a passive margin (New Jersey), enabling detailed examination of the intricate relationships between a wide suite of sedimentary processes and their preserved stratigraphy Includes observational studies which document the processes and strata found on particular margins, in addition to numerical models and laboratory experimentation, which provide a quantitative basis for extrapolation in time and space of insights about continental-margin sedimentation Provides a research resource for scientists studying modern and ancient margins, and an educational text for advanced students in sedimentology and stratigraphy
Download or read book Rifts and Passive Margins written by Michal Nemčok and published by Cambridge University Press. This book was released on 2016-03-02 with total page 619 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a comprehensive synthesis of state-of-the-art information on vitally important hydrocarbon habitats for advanced geology students and researchers, exploration geoscientists, and petroleum managers.
Download or read book Rheology and Deformation of the Lithosphere at Continental Margins written by Garry D. Karner and published by Columbia University Press. This book was released on 2004-03-24 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traditionally, investigations of the rheology and deformation of the lithosphere (the rigid or mechanically strong outer layer of the Earth, which contains the crust and the uppermost part of the mantle) have taken place at one scale in the laboratory and at an entirely different scale in the field. Laboratory experiments are generally restricted to centimeter-sized samples and day- or year-length times, while geological processes occur over tens to hundreds of kilometers and millions of years. The application of laboratory results to geological systems necessitates extensive extrapolation in both temporal and spatial scales, as well as a detailed understanding of the dominant physical mechanisms. The development of an understanding of large-scale processes requires an integrated approach. This book explores the current cutting-edge interdisciplinary research in lithospheric rheology and provides a broad summary of the rheology and deformation of the continental lithosphere in both extensional and compressional settings. Individual chapters explore contemporary research resulting from laboratory, observational, and theoretical experiments.
Download or read book Active Continental Margins Present and Past written by Geologische Vereinigung and published by Springer. This book was released on 2013-12-01 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tectonic Inheritance in Continental Rifts and Passive Margins written by Achyuta Ayan Misra and published by Springer. This book was released on 2015-06-25 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work reviews the mechanism of rifting with a focus on pre-existing tectonic weaknesses in pre-rift and/or basement rocks, i.e., on tectonic inheritance. The passive margins that are studied in this book are the Norwegian Continental Shelf, the Eastern North America and the East and West Indian Continental Margins. The continental rifts that have been analysed are the East African Rift System, the Brazilian Continental Rift Systems and the European Cenozoic Rift System. It states how rifts and passive margins serve as valuable locations for hydrocarbon exploration. Tectonic inheritance/heritage examines the influence of pre-existing/pre-rift elements on the geometry, genesis and propagation of rift-related faults. Such elements include anisotropies in the shallow crustal levels, as well as the rheology of the lithosphere. Inheritance greatly influences the architecture of rifted passive margins including the attitude of faults and geometry of horsts, (half-) grabens, transfer zones etc. Inheritance is also a determining factor in the width of rifts and rift shoulder topography.
Download or read book Historical Earthquakes Tsunamis and Archaeology in the Iberian Peninsula written by Manuel Álvarez-Martí-Aguilar and published by Springer Nature. This book was released on 2022-06-22 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research on historical earthquakes and tsunamis in the Iberian Peninsula has made great strides in recent years, from diverse scientific fields ranging from geology to archaeology. In addition to the famous earthquake and tsunami of 1755, which intensely affected the peninsula, researchers are conducting a growing number of surveys and case studies on seismic episodes and extreme wave events of possible tsunamigenic origin in Portugal and Spain during the ancient, medieval, and modern eras. However, the development of these studies has suffered due to a certain lack of communication among the different fields of research, which are focused on their own methodologies and interests. The aim of this book is to promote interdisciplinary dialogue by linking the results of the most recent research into historical earthquakes and tsunamis in Iberia from the fields of geology, history and archaeology. The volume, which devotes special attention to tsunamis and to events that occurred in the Iberian Peninsula before 1755, offers synthetic insights, updates, and case studies of maximum interest for knowledge of the historical seismology of Portugal and Spain.
Download or read book Leveraging National Oceanographic Capabilities written by United States. Congress. House. Committee on Science. Subcommittee on Energy and Environment and published by . This book was released on 1996 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Andes written by Onno Oncken and published by Springer Science & Business Media. This book was released on 2006-11-22 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the first comprehensive overview of a complete subduction orogen, the Andes. To date the results provide the densest and most highly resolved geophysical image of an active subduction orogen.
