Receptions, from a ship-suspended source (in the band ) to an ocean bottom seismometer (about depth) and the deepest element on a vertical hydrophone array (about above the seafloor) that were acquired on the 2004 Long-Range Ocean Acoustic Propagation Experiment in the North Pacific Ocean, are described. The ranges varied from . In addition to predicted ocean acoustic arrivals and deep shadow zone arrivals (leaking below turning points), “deep seafloor arrivals,” that are dominant on the seafloor geophone but are absent or very weak on the hydrophone array, are observed. These deep seafloor arrivals are an unexplained set of arrivals in ocean acoustics possibly associated with seafloor interface waves.
REFERENCES
1.
Antonov
, J. I.
, Locarnini
, R. A.
, Boyer
, T. P.
, Mishonov
, A. V.
, and Garcia
, H. E.
(2006
). World Ocean Atlas 2005
, Vol. 2
, edited by S.
Levitus
(U.S. Government Printing Office
, Washington, DC
), NOAA Atlas NESDIS 62.2.
Bowles
, F. A.
(1997
). “Observations on attenuation and shear-wave velocity in fine-grained, marine sediments
,” J. Acoust. Soc. Am.
101
, 3385
–3397
.3.
Butler
, R.
(2006
). “Observations of polarized seismoacoustic T waves at and beneath the seafloor in the abyssal Pacific ocean
,” J. Acoust. Soc. Am.
120
, 3599
–3606
.4.
Butler
, R.
, and Lomnitz
, C.
(2002
). “Coupled seismoacoustic modes on the seafloor
,” Geophys. Res. Lett.
29
, 57
–1
57
–4
.5.
Chapman
, N. R.
, and Marrett
, R.
(2006
). “The directionality of acoustic T-phase signals from small magnitude submarine earthquakes
,” J. Acoust. Soc. Am.
119
, 3669
–3675
.6.
Collins
, M. D.
(1989
). “A higher-order parabolic equation for wave propagation in an ocean overlying an elastic bottom
,” J. Acoust. Soc. Am.
86
, 1459
–1464
.7.
Collins
, M. D.
(1991
). “Higher-order Padé approximations for accurate and stable elastic parabolic equations with application to interface wave propagation
,” J. Acoust. Soc. Am.
89
, 1050
–1057
.8.
Collins
, M. D.
(1993
). “A split-step Padé solution for the parabolic equation method
,” J. Acoust. Soc. Am.
93
, 1736
–1742
.9.
Collins
, M. D.
, and Westwood
, E. K.
(1991
). “A higher-order energy-conserving parabolic equation for range-dependent ocean depth, sound speed, and density
,” J. Acoust. Soc. Am.
89
, 1068
–1075
.10.
Colosi
, J. A.
, Baggeroer
, A. B.
, Cornuelle
, B. D.
, Dzieciuch
, M. A.
, Munk
, W. H.
, Worcester
, P. F.
, Dushaw
, B. D.
, Howe
, B. M.
, Mercer
, J. A.
, Spindel
, R. C.
, Birdsall
, T. D.
, Metzger
, K.
, and Forbes
, A. M. G.
(2005
). “Analysis of multipath acoustic field variability and coherence in the finale of broadband basin-scale transmissions in the North Pacific Ocean
,” J. Acoust. Soc. Am.
117
, 1538
–1564
.11.
de Groot-Hedlin
, C.
, Blackman
, D. K.
, and Jenkins
, C. S.
(2009
). “Effects of variability associated with the Antarctic circumpolar current on sound propagation in the ocean
,” Geophys. J. Int.
176
, 478
–490
.12.
Dougherty
, M. E.
, and Stephen
, R. A.
(1988
). “Seismic energy partitioning and scattering in laterally heterogeneous ocean crust
,” Pure Appl. Geophys.
128
, 195
–229
.13.
Dushaw
, B. D.
, Howe
, B. M.
, Mercer
, J. A.
, and Spindel
, R.
(1999
). “Multimegameter-range acoustic data obtained by bottom-mounted hydrophone arrays for measurement of ocean temperature
,” IEEE J. Ocean. Eng.
24
, 202
–214
.14.
Hamilton
, E. L.
(1976
). “Sound attenuation as a function of depth in the seafloor
,” J. Acoust. Soc. Am.
59
, 528
–535
.15.
Heaney
, K. D.
, Kuperman
, W. A.
, and McDonald
, B. E.
(1991
). “Perth–Bermuda sound propagation (1960): Adiabatic mode interpretation
,” J. Acoust. Soc. Am.
90
, 2586
–2594
.16.
Kibblewhite
, A. C.
(1989
). “Attenuation of sound in marine sediments: A review with emphasis on new low-frequency data
,” J. Acoust. Soc. Am.
86
, 716
–738
.17.
Locarnini
, R. A.
, Mishonov
, A. V.
, Antonov
, J. I.
, Boyer
, T. P.
, and Garcia
, H. E.
(2006
). World Ocean Atlas 2005
, Vol. 1
, edited by S.
Levitus
(U.S. Government Printing Office
, Washington, DC
), NOAA Atlas NESDIS 61.18.
Mercer
, J.
, Andrew
, R.
, Howe
, B. M.
, and Colosi
, J.
(2005
). “Cruise report: Long-Range Ocean Acoustic Propagation experiment (LOAPEX)
,” Report No. APL-UW TR 0501, Applied Physics Laboratory, University of Washington
, Seattle, WA.19.
Mercer
, J. A.
, Colosi
, J. A.
, Howe
, B. M.
, Dzieciuch
, M. A.
, Stephen
, R.
, and Worcester
, P. F.
(2009
). “LOAPEX: The Long-Range Ocean Acoustic Propagation Experiment
,” IEEE J. Ocean. Eng.
34
, 1
–11
.20.
Mercer
, J. A.
, Howe
, B. M.
, Andrew
, R. K.
, Wolfson
, M. A.
, Worcester
, P. F.
, Dzieciuch
, M. A.
, and Colosi
, J. A.
(2006
). “The Long-Range Ocean Acoustic Propagation Experiment (LOAPEX): An overview
,” J. Acoust. Soc. Am.
120
, 3020
.21.
Mitchell
, S. K.
, and Focke
, K. C.
(1980
). “New measurements of compressional wave attenuation in deep ocean sediments
,” J. Acoust. Soc. Am.
67
, 1582
–1589
.22.
Munk
, W.
, Worcester
, P.
, and Wunsch
, C.
(1995
). Ocean Acoustic Tomography
(Cambridge University Press
, Cambridge, UK
).23.
Odom
, R. I.
, and Stephen
, R. A.
(2004
). Proceedings, Seismo-Acoustic Applications in Marine Geology and Geophysics Workshop, Woods Hole Oceanographic Institution
, [Report No. APL-UW TR 0406, Applied Physics Laboratory, University of Washington
, Seattle, WA
].24.
Park
, M.
, Odom
, R. I.
, and Soukup
, D. J.
(2001
). “Modal scattering: A key to understanding oceanic T-phases
,” Geophys. Res. Lett.
28
, 3401
–3404
.25.
Schreiner
, M. A.
, and Dorman
, L. M.
(1990
). “Coherence lengths of seafloor noise: Effect of ocean bottom structure
,” J. Acoust. Soc. Am.
88
, 1503
–1514
.26.
Smith
, W. H. F.
, and Sandwell
, D. T.
(1997
). “Global seafloor topography from satellite altimetry and ship depth soundings
,” Science
277
, 1956
–1962
.27.
Stephen
, R. A.
, and Swift
, S. A.
(1994
). “Modeling seafloor geoacoustic interaction with a numerical scattering chamber
,” J. Acoust. Soc. Am.
96
, 973
–990
.28.
Stephen
, R. A.
, Mercer
, J. A.
, Andrew
, R. K.
, and Colosi
, J. A.
(2006
). “Seafloor hydrophone and vertical geophone observations during the North Pacific Acoustic Laboratory/Long-range Ocean Acoustic Propagation Experiment (NPAL/LOAPEX)
,” J. Acoust. Soc. Am.
120
, 3021
.29.
Stephen
, R. A.
, Bolmer
, S. T.
, Udovydchenkov
, I.
, Worcester
, P. F.
, Dzieciuch
, M. A.
, Van Uffelen
, L.
, Mercer
, J. A.
, Andrew
, R. K.
, Buck
, L. J.
, Colosi
, J. A.
, and Howe
, B. M.
(2008
). “NPAL04 OBS data analysis part 1: Kinematics of deep seafloor arrivals
,” Report No. WHOI-2008-03, Woods Hole Oceanographic Institution
, Woods Hole, MA.30.
Swift
, S. A.
, and Stephen
, R. A.
(1994
). “The scattering of a low-angle pulse beam by seafloor volume heterogeneities
,” J. Acoust. Soc. Am.
96
, 991
–1001
.31.
Swift
, S. A.
, Lizarralde
, D.
, Hoskins
, H.
, and Stephen
, R. A.
(1998
). “Seismic attenuation in upper oceanic crust at Hole 504B
,” J. Geophys. Res.
103
, 27193
–27206
.32.
Van Uffelen
, L.
, Worcester
, P.
, and Dzieciuch
, M.
(2008
). “Absolute intensities of acoustic shadow zone arrivals
,” J. Acoust. Soc. Am.
123
, 3464
.33.
Van Uffelen
, L. J.
, Worcester
, P. F.
, Dzieciuch
, M. A.
, and Rudnick
, D. L.
(2009
). “The vertical structure of shadow-zone arrivals at long range in the ocean
,” J. Acoust. Soc. Am.
125
, 3539
–3588
.34.
Van Uffelen
, L. J.
, Worcester
, P. F.
, Dzieciuch
, M. A.
, Rudnick
, D. L.
, Cornuelle
, B. D.
, and Munk
, W. H.
(2006
). “The vertical structure of shadow-zone arrivals at long range in the ocean (A)
,” J. Acoust. Soc. Am.
119
, 3344
.35.
Wage
, K. E.
, Baggeroer
, A. B.
, and Preisig
, J. C.
(2003
). “Modal analysis of broadband acoustic receptions at range in the North Pacific using short-time Fourier techniques
,” J. Acoust. Soc. Am.
113
, 801
–817
.36.
Wage
, K. E.
, Dzieciuch
, M. A.
, Worcester
, P. F.
, Howe
, B. M.
, and Mercer
, J. A.
(2005
). “Mode coherence at megameter ranges in the North Pacific Ocean
,” J. Acoust. Soc. Am.
117
, 1565
–1581
.37.
Wetton
, B. T. R.
, and Brooke
, G. H.
(1990
). “One-way wave equations for seismoacoustic propagation in elastic waveguides
,” J. Acoust. Soc. Am.
87
, 624
–632
.38.
Worcester
, P.
(2005
). “North Pacific Acoustic Laboratory: SPICE04 Recovery Cruise Report
,” Scripps Institution of Oceanography
, La Jolla, CA.39.
Xu
, J.
(2007
). “Effects of internal waves on low frequency, long range, acoustic propagation in the deep ocean
,” Ph.D. thesis, MIT/WHOI Joint Program, Woods Hole, MA.© 2009 Acoustical Society of America.
2009
Acoustical Society of America
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