Acoustic Attenuation in Ocean Sediments Found in Shallow Water Regions
Author : K. C. Focke
Publisher :
Page : pages
File Size : 28,82 MB
Release : 1984
Category : Engineering
ISBN :
Author : K. C. Focke
Publisher :
Page : pages
File Size : 28,82 MB
Release : 1984
Category : Engineering
ISBN :
Author : Karl Crawford Focke
Publisher :
Page : 80 pages
File Size : 32,3 MB
Release : 1983
Category : Marine sediments
ISBN :
The acoustic attenuation in ocean sediments is a major loss mechanism for low frequency acoustic propagation in shallow water regions. Analysis of measured propagation in these regions has generally included estimates of the attenuation in the sediment, without consideration of the variations in attenuation as a function of depth. It will be shown that these variations can have a significant impact on the standard estimates. A new procedure is then developed which provides estimates of the attenuation as a function of depth. This procedure is used to obtain attenuation depth profiles in three shallow water regions. These estimated profiles present characteristics observed in laboratory and in situ measurements
Author : William A. Kuperman
Publisher : Springer Science & Business Media
Page : 700 pages
File Size : 47,56 MB
Release : 2013-03-13
Category : Science
ISBN : 1468490516
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.
Author : Lloyd Hampton
Publisher : Springer Science & Business Media
Page : 568 pages
File Size : 21,98 MB
Release : 2013-03-09
Category : Science
ISBN : 1468408380
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.
Author : Y. Igarashi
Publisher :
Page : 48 pages
File Size : 31,3 MB
Release : 1973
Category : Marine sediments
ISBN :
Measurements were made of sound speed and attenuation in marine sediments at 15, 30, and 60kHz by means of in situ acoustic probe instrumentation in conjunction with CURV II. These experiments were conducted in silty sand and sandy silt Continental Shelf areas of the Santa Barbara Channel, California. The main conclusions are: (1) attenuation was found to be about 3, 10, and 20 dB per meter at 15, 30, and 60 kHz, respectively; (2) for the attenuation equation, alpha = K(f to the nth power) (where alpha is sound attenuation in dB per meter, K is a dimensional material parameter, and f is frequency in kHz), the exponent, n, was found to be about 1.2, and K varied from approximately 0.1 to 0.2; (3) no significant sound-speed dispersion was found, in agreement with many other investigations; and (4) individual acoustic measurements made in close proximity to one another in a nominally homogeneous bottom can vary appreciably, although their average values may be in close agreement. (Author).
Author : Edwin Lee Hamilton
Publisher :
Page : 28 pages
File Size : 44,47 MB
Release : 1975
Category : Marine sediments
ISBN :
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.
Author : Karl C. Focke
Publisher :
Page : 76 pages
File Size : 49,71 MB
Release : 1988
Category : Seawater
ISBN :
Author : R. L. Allman
Publisher :
Page : 52 pages
File Size : 44,2 MB
Release : 1984
Category : Attenuation (Physics)
ISBN :
Author : Robert J. Urick
Publisher :
Page : 272 pages
File Size : 45,29 MB
Release : 1979
Category : Sound
ISBN :
Author :
Publisher :
Page : 500 pages
File Size : 42,65 MB
Release : 1995
Category : Aeronautics
ISBN :