Download or read book Refraction of Sound in the Sea Floor written by Roger Ervin Christensen and published by . This book was released on 1975 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major mode of propagation of acoustic energy at low frequencies is a shallow refracted path through unconsolidated sediments of the sea floor. Successful modelling of the bottom-refracted mode of propagation, requires knowledge of the sediment thickness, sound velocity, and acoustic attenuation in the sediments. Unconsolidated sediments may be considered an extension of the water column with the acoustic floor of the ocean being the base of the unconsolidated sediments. Observed bottom loss results from two Pacific Ocean sites of differing sediment thickness are discussed. Lower losses noted at the low grazing angles from the thick sediment station are attributed to added acoustic energy that is received from shallow bottom-refracted arrivals. Lower losses noted at the high grazing angles from the thin sediment station, on the other hand, are attributed to added acoustic energy that is received from subbottom reflections occurring at the base of the unconsolidated sediments. (Author).
Download or read book Sound Propagation in the Sea written by Robert J. Urick and published by . This book was released on 1979 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sound Images of the Ocean written by Peter Wille and published by Springer Science & Business Media. This book was released on 2005-12-06 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sound Images of the Ocean is the first comprehensive overview of acoustic imaging applications in the various fields of marine research, utilization, surveillance, and protection. The book employs 400 sound images of the sea floor and of processes in the sea volume, contributed by more than 120 marine experts from 22 nations.
Download or read book Physics of Sound in Marine Sediments written by Lloyd Hampton and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: The phenomenon of sound transmissions through marine sediments is of extreme interest to both the United States civilian and Navy research communities. Both communities have conducted research within the field of this phenomenon approaching it from different perspectives. The academic research community has approached it as a technique for studying sedimentary and crustal structures of the ocean basins. The Navy research community has approached it as an additional variable in the predictability of sound trans mission through oceanic waters. In order to join these diverse talents, with the principal aim of bringing into sharp focus the state-of-the-science in the problems relating to the behavior of sound in marine sediments, the Office of Naval Research organized and sponsored an invited symposium on this subject. The papers published in this volume are the results of this symposium and mark the frontiers in the state-of-the-art. The symposia series were based on five research areas identified by ONR as being particularly suitable for critical review and for the appraisal of future research trends. These areas include: 1. Physics of Sound in Marine Sediments, 2. Physical and Engineering Properties of Deep-Sea Sediments, 3. The Role of Bottom Currents in Sea Floor Geological Processes, 4. Nephelometry and the Optical Properties of the Ocean I'laters, S. Natural Gases in Marine Sediments and Their Mode of Distribution. These five areas also form some of the research priorities of the ONR program in Marine Geology and Geophysics.
Download or read book Fundamentals of Ocean Acoustics written by L. Brekhovskikh and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: The continents of our planet have already been exploited to a great extent. Therefore man is turning his sight to the vast spaciousness of the ocean whose resources - mineral, biological, energetic, and others - are just beginning to be used. The ocean is being intensively studied. Our notions about the dynam ics of ocean waters and their role in forming the Earth's climate as well as about the structure of the ocean bottom have substantially changed during the last two decades. An outstanding part in this accelerated exploration of the ocean is played by ocean acoustics. Only sound waves can propagate in water over large distances. Practically all kinds of telemetry, communication, location, and re mote sensing of water masses and the ocean bottom use sound waves. Propa gating over thousands of kilometers in the ocean, they bring information on earthquakes, eruptions of volcanoes, and distant storms. Projects using acoustical tomography systems for exploration of the ocean are presently be ing developed. Each of these systems will allow us to determine the three-di mensional structure of water masses in regions as large as millions of square kilometers.
Download or read book Acoustic and Related Properties of the Sea Floor written by Edwin Lee Hamilton and published by . This book was released on 1975 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The general objectives of this investigation were to determine and study those characteristics of the sea floor that affect sound propagation and the prediction of sonar performance; to support underwater acoustics' experiments and theory by furnishing information on the mass physical properties of sediments and rocks in the form of geoacoustic models of the sea floor; and to develop models of the sea floor which include gradients of sound velocity and attenuation, density, and elastic properties. Specifically, the minor objectives were to revise and review earlier work on the relations between frequency and attenuation of compressional (sound) waves in marine sediments and on the relations between attenuation and sediment porosity. The major objectives were to determine and predict variations of the attenuation of sound waves with depth in the sea floor.
Download or read book Sound Propagation in the Sea written by Robert J. Urick and published by Peninsula Pub. This book was released on 1982 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rated the most up-to-date source on underwater sound propagation in the current literature. The book covers these topics and more: Basic theory; velocity of sound in the ocean; attenuation and absorption; computer models of sound propagation; reflections and scattering by the sea surface and the sea bottom; temporal and spatial coherence; and multipath in the sea.
Download or read book Ocean Acoustics written by J.A. DeSanto and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Topics volume is devoted to a study of sound propagation in the ocean. The effect of the interior of the ocean on underwater sound is analogous to the effect of a lens on light. The oceanic lens is related, as in light propagation, to the index of refraction of the medium. The latter is giv~n by the ratio of the sound frequency to the speed of sound in water, typi ca lly about 1500 m s -1. It is the vari ation of the sound speed due to changing temperature, density, salinity, and pres sure in the complex ocean environment which creates the lens effect. Many oceanic processes such as currents, tides, eddies (circulating, translating regions of wa ter), and internal waves (the wave-like structure of the oceanic density variabil ity) contri bute in turn to the changes in sound speed'. The net effect of the ocean lens is to trap and guide sound waves in a channel created by the lens. The trapped sound can then propagate thousands of miles in this oceanic waveguide. In addition to the propagation in the interior of the ocean, sound can propagate into and back out of the ocean bottom as well as scatter from the ocean surface. Just as the sound produced by a loudspeaker in a room is affected by the walls of the room, so the ocean boundaries and the material properties below the ocean bottom are essential ingredients in the problem.
Download or read book Bottom Interacting Ocean Acoustics written by William A. Kuperman and published by Springer Science & Business Media. This book was released on 2013-03-13 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: vi These categories seem to represent the basic breakdown by field of present-day research in this area. Though each paper has been classified into one of these categories (for conference organization purpose), many papers overlapped two or three areas. It is also interesting to note that not only are scientific results being communicated, but the latest techniques and the state-of-the-art tools of the trade (existing and in development) are also being presented. The forty-six papers presented at this conference represent the work of seventy scientists working at universities, government laboratories, and industrial laboratories in seven different countries . We would like to thank the contributors for their efforts and especially for their promptness in providing the editors with their final manuscripts. William A. Kuperman Finn B. Jensen La Spezia, Italy July 1980 CONTENTS GEOACOUSTIC PROPERTIES OF MARINE SEDIMENTS Attenuation of Sound in Marine Sediments . • 1 J. M. Hovem Directivity and Radiation Impedance of a Transducer 15 Embedded in a Lossy Medium . •• •••••• G. H. Ziehm Elastic Properties Related to Depth of Burial, Strontium Content and Age, and Diagenetic Stage in Pelagic Carbonate Sediments . . • • . • • • . 41 M. H. Manghnani, S. O. Schianger, and P. D. Milholland Application of Geophysical Methods 'and Equipment to Explore the Sea Bottom . •• •••. • 53 H. F. Weichart The Acoustic Response of Some Gas-Charged Sediments in the Northern Adriatic Sea • • • • . • • • • 73 A.
Download or read book Sounds in the Sea written by Herman Medwin and published by Cambridge University Press. This book was released on 2005-07-21 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publisher Description
Download or read book Physics of Sound in the Sea written by Research Analysis Group and published by . This book was released on 1969 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Springer Handbook of Acoustics written by Thomas Rossing and published by Springer Science & Business Media. This book was released on 2007-06-21 with total page 1179 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an unparalleled modern handbook reflecting the richly interdisciplinary nature of acoustics edited by an acknowledged master in the field. The handbook reviews the most important areas of the subject, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest research and applications are incorporated throughout, including computer recognition and synthesis of speech, physiological acoustics, diagnostic imaging and therapeutic applications and acoustical oceanography. An accompanying CD-ROM contains audio and video files.
Download or read book Fundamentals of Acoustical Oceanography written by Herman Medwin and published by Academic Press. This book was released on 1997-11-05 with total page 739 pages. Available in PDF, EPUB and Kindle. Book excerpt: The developments in the field of ocean acoustics over recent years make this book an important reference for specialists in acoustics, oceanography, marine biology, and related fields. Fundamentals of Acoustical Oceanography also encourages a new generation of scientists, engineers, and entrepreneurs to apply the modern methods of acoustical physics to probe the unknown sea. The book is an authoritative, modern text with examples and exercises. It contains techniques to solve the direct problems, solutions of inverse problems, and an extensive bibliography from the earliest use of sound in the sea to present references.Written by internationally recognized scientists, the book provides background to measure ocean parameters and processes, find life and objects in the sea, communicate underwater, and survey the boundaries of the sea. Fundamentals of Acoustical Oceanography explains principles of underwater sound propagation, and describes how both actively probing sonars and passively listening hydrophones can reveal what the eye cannot see over vast ranges of the turbid ocean. This book demonstrates how to use acoustical remote sensing, variations in sound transmission, in situ acoustical measurements, and computer and laboratory models to identify the physical and biological parameters and processes in the sea. * Offers an integrated, modern approach to passive and active underwater acoustics* Contains many examples of laboratory scale models of ocean-acoustic environments, as well as descriptions of experiments at sea* Covers remote sensing of marine life and the seafloor* Includes signal processing of ocean sounds, physical and biological noises at sea, and inversions* resents sound sources, receivers, and calibration* Explains high intensities; explosive waves, parametric sources, cavitation, shock waves, and streaming* Covers microbubbles from breaking waves, rainfall, dispersion, and attenuation* Describes sound propagation along ray paths and caustics* Presents sound transmissions and normal mode methods in ocean waveguides
Download or read book The Sea Volume 4A New Concepts of Sea Floor Evolution written by Arthur E. Maxwell and published by Harvard University Press. This book was released on 1971 with total page 814 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acoustic Interactions with Submerged Elastic Structures written by Ardshir Guran and published by World Scientific. This book was released on 2001 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: "\berall's work in acoustic and electromagnetic scattering has evoked much interest, in the US as well as abroad, because of its possible practical applications, as well as the theoretical understanding. Many collaborators have been inspired by it, and have now contributed to this volume. The book is an excellent contribution to the literature of Acoustics and Wave Propagation. Professor Guran is to be congratulated for organizing and editing this volume." Prof. Hans A Bethe Noble Laureate Cornell University, 1996
Download or read book Ocean Seismo Acoustics written by T. Akal and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 898 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seafloor investigation has long been a feature of not only seismology but also of acoustics. Indeed it was acoustics that produced depth sounders, giving us the first capability of producing both global and local maps of the seafloor. Subsequently, better instrumentation and techniques led to a clearer, more quantitative picture of the seabed itself, which stimulated new hypotheses such as seafloor spreading through the availability of more reliable data on sediment thickness over ocean basins and other bottom features. Geologists and geophysicists have used both acoustic and seismic methods to study the seabed by considering the propagation of signals arising from both natural seismic events and man-made impulsive sources. Although significant advances have been made in instrumentation, such as long towed geophysical arrays, ai r guns and ocean bot tom seismometers, the pic ture of the seafloor is still far from complete. Underwater acoustics concerns itself today with the phenomena of propagation and noise at frequencies and ranges that require an understanding of acoustic interaction at both of its boundaries, the sea surface and seafloor, over depths ranging from tens to thousands of meters. Much of the earlier higher frequency (>1 kHz) work included the characterization of the seafloor in regimes of reflection coefficients which were empirically derived from surveys. The results of these studies met with only limited success, confined as they were to those areas where survey data existed and lacking a physical understanding of the processes of reflection and scattering.
Download or read book Sound Propagation in the Sea written by Robert J. Urick and published by . This book was released on 1979 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
