Bottom-Interacting Ocean Acoustics

699 Pages·1981·23.01 MB·English

by  Jens M. Hovem (auth.)

BOTTOM-INTERACTING
OCEAN ACOUSTICS
NATO CONFERENCE SERIES
Ecology
II Systems Science
III Human Factors
IV Marine Sciences
V Air-Sea Interactions
VI Materials Science
IV MARINE SCIENCES
Vo/ume 1 Marine Natural Products Chemistry
edited by D. J. Faulkner and W. H. Fenical
Vo/ume 2 Marine Organisms: Genetics, Ecology, and Evolution
edited by Bruno Battaglia and John A. Beardmore
Vo/ume 3 Spatial Pattern in Plankton Communities
edited by John H. Steele
Vo/ume 4 Fjord Oceanography
edited by Howard J. Freeland, David M. Farmer, and
Colin D. Levings
Vo/ume 5 Bottom-Interacting Ocean Acoustics
edited by William A. Kuperman and Finn B. Jensen
BOTTOM-INTERACTING
OCEAN ACOUSTICS
Edited by
William A. Kuperman
and
Finn B. Jensen
SACLANT ASW Research Centre
La Spezia, Italy
Published in cooperation with NATO Scientific Affairs Division by
PLENUM PRESS· NEW YORK AND LONDON
Library of Congress Cataloging in Publ ication Data
Nato Conference on Bottom-Interacting Ocean Acoustics, La Spezia, 1980.
Bottom-interacting ocean acoustics.
(NATO conference series: IV, Marine sciences; v. 5)
"Proceedings of the NATO Conference ... held at the NATO SACLANT ASW Re
search Centre, La Spezia, Italy, June 9-12,1980."
Includes indexes.
1. Underwater acoustics-Congresses. 2. Ocean bottom-Congresses. I. Kuperman,
William A. 11. Jensen, Finn Brunn. 111. Title. IV. Series.
QC242.N37 1980 551.46'01 80-24616
ISBN 978-1-4684-9053-4 ISBN 978-1-4684-9051-0 (eBook)
DOI 10.1007/978-1-4684-9051-0
Proceedings of a conference on Bottom-Interacting Ocean
Acoustics held June 9-12, 1980, at the NATO SACLANT ASW
Research Centre, La Spezia, Italy.
© 1980 Plenum Press, New Y ork
Softcover reprint of the hardcover 1s t edition 1980
A Division of Plenum Publishing Corporation
227 West 17th Street, New York, N.Y. 10011
All rights reserved
No part of this book may be reproduced, stored in a retrieval system, or transmitted,
in any form or by any means, electronic, mechanical, photocopying, microfilming,
recording, or otherwise, without written permission from the Publisher
P R E F ACE
This book contains the complete proceedings of a conference
held at the NATO SACLANT ASW Research Centre, La Spezia, Italy on
9-12 June, 1980. The Centre has traditionally organized many
conferences in the field of marine physics and has published the
proceedings in its own series of Conference Proceedings. For the
present conference the NATO Scientific Affairs Division has kindly
agreed to allow the proceedings to be published in their NATO
Conference Series, even though the conference was sponsored by
SACLANTCEN and not by the Scientific Affairs Division.
In re cent years bottom-interacting ocean acoustics has become
a research area of intensely increasing interest. This research
area can be broken down into two basic fields: research using
acoustics to probe the ocean bot tom and research aimed at
determining how the ocean bottom affects sound propagation in the
ocean. Obviously, much of the information obtained in either of
the two fields is of interest to researchers in both fields. It
was therefore the intent of this conference to assemble as much
state-of-the-art information as possible from both fields so as to
stimulate further research in this area. In order to accomplish
this, we originally called for papers in the following traditional
fields:
.Coastal-water acoustics
.Low-frequency deep-water acoustics involving bottom
interaction
.Acoustic properties of marine sediments
.Ocean seismic studies as related to ocean acoustics
.Signal-processing techniques that include the effects
of bot tom interaction
For the conference and the present proceedings we decided to
re-categorize the papers as folIows:
.Geoacoustic properties of marine sediments
.Bottom loss: reflection and refraction
.Bottom-interface and seismic-wave propagation
.Acoustic modelling
.Sound propagation: techniques and experiment vs theory
.Fluctuations, coherence and signal processing
v
vi PREFACE
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
Embedded in a Lossy Medium . •• •••••• 15
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. Stefanon
Simultaneous Application of Reflection Strength
Recorder, Sidescan Sonar and Sub-Bottom
Profiler in Sea-Floor Sediment Mapping 85
K. Winn, F.C. Kögler, and F. Werner
Results and Methods Used to Determine the Acoustic
Properties of the Southeast Asian Margins 99
R.E. Houtz
Circular Structures Observed in the Deep Sea by
the Swathmap Long-Range Sidescan Sonar 111
J.E. Andrews and P. Humphrey
vii
viii CONTENTS
BOTTOM LOSS: REFLECTION AND REFRACTION
A Perspective on Bottom Reflectivity and
119
Backscattering . . . . . . . .
J.J. Hanrahan
Some Bottom-Reflection Loss Anomalies Near Grazing
and their Effect on Propagation in Shallow
Water 135
O.F. Hastrup
Determination of Sediment Sound Speed Profiles
Using Caustic Range Information . . . . 153
G.V. Frisk
Inference of Geo-Acoustic Parameters from Bottom-
Loss Data . . . . 159
C. W. Spofford
Attenuation Estimates from High Resolution Sub
Bottom Profiler Echoes . . . . 173
D.J. Dodds
Low Frequency Bottom Reflectivity Measurements ~n
the Tufts Abyssal Plain . . . . . 193
N.R. Chapman
Resonances in Acoustic Bottom Reflection and their
Relation to the Ocean Bottom Properties 209
W.R. Hoover, A. Nagl, and H. liberall
Comparison of Synthetic and Experimental Bottom
Interactive Waveforms . . . . 225
F.R. DiNapoli, D. Potter, and P. Herstein
Reflection and Refraction of Parametrically
Generated Sound at a Water-Sediment Interface 239
J.N. Tj~tta and S. Tj~tta
Transmission of a Narrow Beam of Sound across the
Boundary between two Fluids 259
H.O. Berktay and A.H.A. Moustafa
CONTENTS ix
BOTTOM-INTERFACE AND SEISMIC-WAVE PROPAGATION
Experimental Determination of Properties of the
Scholte Wave in the Bottom of the North Sea 285
F. Schirmer
Model Computations for Low-Velocity Surface Waves
on Marine Sediments . . . . . . . . . 299
H.H. Essen
Experimental and Theoretical Studies of Seismic
Interface Waves in Coastal Waters . . . . 307
D. Rauch
Ambient and Ship-Induced Low-Frequency Noise in
Shallow Water . . . . . . . . . . . . . . 329
B. Schmalfeldt and D. Rauch
Dispersion of One-Second Rayleigh Modes through
Oceanic Sediments Following Shallow Earth
quakes in the South-Central Pacific Ocean
Basin . . . . . . . . . 345
E.A. Okal and J. Talandier
Velocity Spectral Estimates from the Arrays of
the ROSE Program . . . . . . . . 359
A.B. Baggeroer
ACOUSTIC MODELLING
Bottom Interaction Represented by Impedance
Conditions in Normal-Mode Calculations 377
D.F. Gordon and D. White
Cycle Distance in Guided Propagation 393
D.E. Weston
Computations of Averaged Sound-Propagation Losses
and Frequency/Space Coherence Functions in
Shallow Waters . . . . . . • . . • . 399
R. Laval and Y. Labasque
Initial Data for the Parabolic Equation 417
D.H. Wood and J.S. Papadakis
The Seamount as a.piffracting Body 421
H. Medwin and R.P. Spaulding, Jr.
x CONTENTS
Propagation of Sound from a Fluid Wedge into a
Fast Fluid Bottom • • • . • • . • • . 439
A.B. Coppens and J.V. Sanders
Range-Dependent Bottom-Limited Propagation
Modelling with the Parabolic Equation 451
F.B. Jensen and W.A. Kuperman
SOUND PROPAGATION: TECHNIQUES AND EXPERIMENT VS THEORY
A Low-Frequency Parametric Research Tool for
Ocean Acoustics . . . . • 467
T.G. Muir, L.A. Thompson, L.R. Cox,
and H.G. Frey
Transmission Loss Variability 1n Shallow Water . . • . . .• 485
J.E. Allen
Influence of Semiconsolidated Sediments on Sound
Propagation in a Coastal Region 493
S.T. McDaniel and J.H. Beebe
Geoacoustic Models of the Seabed to Support Range
Dependent Propagation Studies on the
Scotian Shelf ..•......•.•.. 507
J.H. Beebe and S.T. McDanie1
Propagation Loss Modelling on the Scotian Shelf:
the Geo-Acoustic Model . . . . . . • . • • 525
D.M.F. Chapman and D.D. Ellis
Propagation Loss Modelling on the Scotian Shelf:
Comparison of Model Predictions with
Measurements . . • . . . • . . . • . 541
D.D. Ellis and D.M.F. Chapman
Sea Floor Effects on Shallow-Water Acoustic
Propagation ..•....•••.. 557
T. Akal
Broadband Model/Data Comparisons for Acoustic
Propagation in Coastal Waters .••• 577
M.C. Ferla, G. Dreini, F.B. Jensen,
and W.A. Kuperman
Computer Model Predictions of Ocean Basin Rever
beration for Large Underwater Explosions • 593
J.A. Goertner