Download or read book Laboratory and in Situ Sediment Acoustics written by Donald J. Shirley and published by . This book was released on 1977 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: During this reporting period, research was directed towards measuring sediment acoustic parameters in situ. Four field trips were made to use the ARL profilometer to make in situ sound speed measurements. Laboratory work continued to add the capability of measuring shear wave speed and acoustic impedance to the existing profilometer. Shear wave and compressional wave data measured in laboratory sediments are reported.
Download or read book Acoustics of in Situ and Laboratory Sediments written by Donald J. Shirley and published by . This book was released on 1978 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the period 1 January to 31 December, 1977, work under Contract N00014-76-C-0117 consisted of three parts: (1) in situ determination of compressional wave speed in ocean sediments using the ARL:UT profilometer; (2) development of transducers to measure shear wave and acoustic impedance parameters of sediments both in situ and in the laboratory; and (3) laboratory measurement of shear wave and compressional wave parameters of real and artificial sediments. Data obtained for the three parts of the program are reported.
Download or read book Acoustical Properties of Laboratory and in Situ Sediments written by P. J. Vidmar and published by . This book was released on 1983 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes work done during the period 1 August 1975-30 June 1983. Major accomplishments include: Development and use of instrumentation to perform in situ measurements of acoustical parameters of marine sediments, measurement of shear and compressional wave parameters of laboratory sediments, development of theoretical descriptions of acoustic propagation in sediments, and laboratory experiments to test various theoretical models of propagation in sediments.
Download or read book Strength Testing of Marine Sediments written by Ronald C. Chaney and published by ASTM International. This book was released on 1985 with total page 561 pages. Available in PDF, EPUB and Kindle. Book excerpt: Philadelphia, PA : ASTM, 1985.
Download or read book Laboratory and Field Studies of Sediment Acoustics written by Donald J. Shirley and published by . This book was released on 1979 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: Work under Contract consisted of three parts: (1) redesign and updating of the ARL:UT profilometer system used to measure in situ sound velocities of ocean bottom sediments, (2) development of transducers to measure shear wave and acoustic impedance parameters of sediments, and (3) laboratory measurements to develop and confirm theoretical models for acoustic propagation in sediments. Data obtained for the three parts of the program are reported.
Download or read book Sound Velocity Elasticity and Related Properties of Marine Sediments North Pacific written by Edwin Lee Hamilton and published by . This book was released on 1969 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sediment Acoustics written by and published by . This book was released on 1980 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the period 1 January - 31 December 1979, work under Contract N00014-76-C-0117 consisted of three parts: (1) use of the profilometer system to obtain in situ compressional wave data and to test in situ shear wave transducers, (2) development of theoretical models for acoustic propagation in sediments, and (3) laboratory measurements of compressional wave and shear wave parameters in laboratory sediments. Data obtained for the three parts of the program are reported. (Author).
Download or read book Laboratory Measurements of Sound Speed and Attenuation of Water saturated Granular Sediments written by Theodore F. Argo and published by . This book was released on 2012 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt: The propagation of acoustic waves through water-saturated granular sediments has been widely studied, yet existing propagation models can not adequately predict the speed and attenuation of sound across the range of frequencies of interest in underwater acoustics, especially in loosely packed sediments that have been recently disturbed by storms or wave action. Advances in modeling are currently dependent on experimental validation of various components of existing models. To begin to address these deficiencies, three well-controlled laboratory experiments were performed in gravity-settled glass beads and reconstituted sand sediments. Sound speed and attenuation measurements in the 0.5 kHz to 10 kHz range are scarce in the literature, so a resonator method was used to investigate a reconstituted sand sediment in this range. The literature contains laboratory and in situ measurements of sound speed and attenuation at higher frequencies, but existing models can not predict both the speed of sound and attenuation simultaneously in some sediments. A time-of-flight technique was used to determine the speed of sound and attenuation in monodisperse water-saturated glass beads, binary glass bead mixtures, and reconstituted sediment samples in the frequency range 200 kHz to 900 kHz to investigate the effect of sediment inhomogeneity. The effect of porosity, independent of changes in other sediment physical properties, has not been demonstrated in the experimental literature. Therefore, a fluidized bed technique was used to independently vary the porosity of monodisperse glass bead samples from 0.37 to 0.43 and a Fourier phase technique was used to determine the speed and attenuation of sound. Collecting these results together, measured sound speeds showed positive dispersion below 50 kHz while negative dispersion was observed above 200 kHz for some samples. Attenuation measurements showed an approximately f0̇5 dependence in the low frequency regime and an approximately f3̇5 dependence for large-grained samples in the high frequency regime. The laboratory experiments presented in this work demonstrate that both sound speed and attenuation in idealized loosely packed water-saturated sediments can not be simultaneously predicted by existing models within the uncertainties of the model input parameters, but the independent effect of porosity on sound speed can be predicted.
Download or read book Acoustical Properties of Sediments written by and published by . This book was released on 1982 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work consisted of (1) final development of the ARL:UT profilometer recorder and transducer to enable the in situ measurement of compressional wave, shear wave, acoustic impedance, and static shear strength of ocean bottom sediments during geophysical coring, and (2) laboratory acoustical measurements on artificial sediments to test predictions of the Hovem model when the pore fluid viscosity is varied. The new profilometer recorder and transducer are described in detail as well as the microcomputer band playback system. Data obtained from the laboratory measurements are displayed.
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 Arbeitsgruppe Gro m rkte im deutschen St dtetag Landeshauptstadt M nchen Internationale Gro markttagung M nchen 1955 written by and published by . This book was released on 1955 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sediment Acoustics written by Robert D. Stoll and published by Springer. This book was released on 1989-12-15 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sediment Acoustics describes the development of a mathematical model to be used to predict the propagation characteristics of acoustic waves in marine sediments. The model is based on the classical theory of Maurice Biot. Over the past 20 years, R.D. Stoll has published many technical papers covering various stages of development and different applications of Biot's theory. This work is summarized in one reference volume for the first time and presents enough introductory material so that researchers and students may use the model without extensive literature searches. Scientists working in the areas of acoustical oceanography, marine seismology, and ocean engineering will find this monograph useful in predicting the wave velocity and attenuation of seafloor sediments based on the geology of an area and such measurable physical properties as porosity and geostatic stress. A simple, interactive computer program is given as an aid in calculating velocity and attenuation, and a number of examples from recent field experiments are presented so that the predictions of the model may be compared with the "ground truth."
Download or read book In Situ Sediment Attenuation and Sound Velocity Ratio Measured in Shallow Water at the Quinault Range written by R. L. Allman and published by . This book was released on 1984 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Equipment for in Situ Measurement of Sediment Sound Velocity and Attenuation written by Richard L. Allman and published by . This book was released on 1974 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental system has been developed that makes possible the in situ collection of acoustic data in marine sediments, with greater convenience and accuracy than has been obtainable by laboratory analysis of bottom core samples. The feasibility of the system, operating in conjunction with the NUC Cable-Controlled Underwater Research Vehicle (CURV II), has been demonstrated. System capabilities are discussed.
Download or read book In Situ High frequency Acoustic Propagation Measurements in Marine Sediments in the Santa Barbara Shelf California written by Y. Igarashi and published by . This book was released on 1973 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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).
Download or read book Geoacoustic Models of the Sea Floor written by E. L. Hamilton and published by . This book was released on 1965 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The information and technology necessary to derive a valid geological-geophysical-acoustic model of the sea floor are presented. Two contrasting models are detailed and discussed: one in the Bering Sea which has a shallow-water, high-velocity, hard-sand bottom; and the Mohole (Guadalupe Site) model which has a deep-water, low-velocity, soft-clay bottom. Other models are to be reported in a continuing series. (Author).
Download or read book Methods and advances in marine geology and hydrodynamics environment written by Nan Wu and published by Frontiers Media SA. This book was released on 2024-01-29 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
