Shear Waves in Marine Sediments


Book Description

Shear waves and closely related interface waves (Rayleigh, Stoneley and Scholte) play an important role in many areas of engineering, geophysics and underwater acoustics. In some cases interest is focused on large-amplitude waves of low frequency such as those associ ated with earthquakes and nuclear explosions; in other cases low amplitude waves, which have often travelled great distances through the sediment, are of interest. Both low and high frequency shear and interface waves are often used for seafloor probing and sediment characterization. As a result of the wide spectrum of different interests, different disciplines have developed lines of research and a literature particularly suited to their own problems. For example water-column acousticians view the seafloor sediment as the lower boundary of their domain and are interested in shear and interface waves in the near bottom sediments mainly from the standpoint of how they influence absorption and reflection at this boundary. On the other hand, geophysicists seeking deep oil deposits are interested in the maximum penetration into the sediments and the tell-tale characteristics of the seismic waves that have encountered potential oil or gas bearing strata. In another area, geotechnical engineers use shear and interface waves to study soil properties necessary for the design and the siting of seafloor structures.







Microstructure of Fine-Grained Sediments


Book Description

Knowledge of basic clay microstructure is fundamental to an understanding of the physical, chemical, and mechanical properties of fine-grained sediments and rocks. This compilation of fifty-nine peer-reviewed papers examines clay microstructure in detail with comprehensive sections focusing on microstructure signatures, environmental processes, modeling, measurement techniques, and future research recommendations. Many of these topics are discussed in light of geological and engineering applications, such as hazardous waste disposal, construction techniques, and drilling programs. The field of clay microstructure is developing rapidly. The concepts, observations, and principles presented in this book will help stimulate new thought and be a "spring board" for exciting new research.




In Situ Determinations of the Velocities of Compressional and Shear Waves in Marine Sediments from a Research Submersible


Book Description

In situ measurements were made of the velocity and attenuation of compressional waves and of velocities of Stoneley waves (from which shear-wave velocities were computed) at six stations in the sea floor off San Diego, California. Water depths ranged from 20 to 1130 meters, and sediment types ranged from medium sand to clayey silt. Sediment densities, porosities, and grain sizes were measured in samples taken at each station. The unique data obtained allowed tentative evaluations of models and equations, and computation of constants, for elastic and viscoelastic saturated, porous media. (Author).




Mechanics of Coastal Sediment Transport


Book Description

This book treats the subject of sediment transport in the marine environment, covering transport of non-cohesive sediment by waves and current in- and outside the surf zone. It can be read independently, but a background in hydraulics and basic wave mechanics is required. It is intended for M.Sc. and Ph.D. students. The primary aim of the book is to describe the physical processes of sediment transport and how to represent them in mathematical models. It does not present a large number of different formulae for the sediment transport rates under various conditions. The book can be divided in two main parts; in the first, the relevant hydrodynamic theory is described; in the second, sediment transport and morphological development are treated. The hydrodynamic part contains a review of elementary theory for water waves, chapters on the turbulent wave boundary layer and the turbulent interaction between waves and currents, and finally, surf zone hydrodynamics and wave driven currents. The part on sediment transport introduces the basic concepts (critical bed shear stress, bed load, suspended load and sheet layer, near-bed concentration, effect of sloping bed); it treats suspended sediment in waves and current and in the surf zone, and current and wave-generated bed forms. Finally, the modelling of cross-shore and long-shore sediment transport is described together with the development, of coastal profiles and coastlines.







Carbonate Seismology


Book Description

In this volume, the geologic framework is established with review papers by experts in carbonate generation, rock properties, sequence and seismic stratigraphy, and structural deformation. Then seismic expression of carbonate terranes is explored in case studies showing the importance of integrating seismic and petrophysical control with geologic models.




Rifting and Sediments in the Red Sea and Arabian Gulf Regions


Book Description

Rifting and Sediments in the Red Sea and Arabian Gulf Regions is a unique text that covers a wide range of topics related to the tectonics and geology of the Red Sea and Arabian (Persian) Gulf region. This book is a collection of invited and peer-reviewed chapters contributed by active researchers around the world. The topics covered in this book include tectonics, magmatism, and lithology, particularly in the Red Sea area. The book also delves into the sediments and evaporites of the Red Sea and Gulf. As the area around the Arabian Peninsula is prone to earthquakes, the seismic hazard estimated in the Red Sea region is also covered by several chapters. Each chapter presents new data and offers extensive lists of references for the reader to explore further. With the ongoing debates regarding the structure of the Red Sea, this book serves as an excellent resource for researchers and any individuals interested in the geology of these two unique seas.




Atlas of Structural Geological Interpretation from Seismic Images


Book Description

This comprehensive book deals primarily with reflection seismic data in the hydrocarbon industry. It brings together seismic examples from North and South America, Africa, Europe, Asia and Australia and features contributions from eleven international authors who are experts in their field. It provides structural geological examples with full-color illustrations and explanations so that students and industry professionals can get a better understanding of what they are being taught. It also shows seismic images in black and white print and covers compression related structures. Representing a compilation of examples for different types of geological structures, Atlas of Structural Geological Interpretation from Seismic Images is a quick guide to finding analogous structures. It provides extensive coverage of seismic expression of different geological structures, faults, folds, mobile substrates (shale and salt), tectonic and regional structures, and common pitfalls in interpretation. The book also includes an un-interpreted seismic section for every interpreted section so that readers can feel free to draw their own conclusion as per their conceptualization. Provides authoritative source of methodologies for seismic interpretation Indicates sources of uncertainty and give alternative interpretations Directly benefits those working in petroleum industries Includes case studies from a variety of tectonic regimes Atlas of Structural Geological Interpretation from Seismic Images is primarily designed for graduate students in Earth Sciences, researchers, and new entrants in industry who are interested in seismic interpretation.




High-Frequency Seafloor Acoustics


Book Description

This book is a research monograph on high-Frequency Seafloor Acoustics. It is the first book in a new series sponsored by the Office of Naval Research on the latest research in underwater acoustics. It provides a critical evaluation of the data and models pertaining to high-frequency acoustic interaction with the seafloor, which will be of interest to researchers in underwater acoustics and to developers of sonars. Models and data are presented so as to be readily usable, backed up by extensive explanation. Much of the data is new, and the discussion in on two levels: concise descriptions in the main text backed up by extensive technical appendices.