Acoustic energy from underwater earthquakes and explosions can propagate over long distances with very little attenuation in the deep ocean. When this sound encounters a seamount, island, or continental margin, it can scatter and again propagate over long distances. Hydrophones in the deep sound channel can detect these reflections tens of minutes or hours after arrivals from the direct source-to-receiver path. This paper presents the Reflected Energy Prediction (REP) model, a model for predicting these reflected arrivals. For a given source and receiver, the REP model uses a detailed knowledge of the underwater environment and components of the Hydroacoustic Coverage Assessment Model, HydroCAM, to predict the impulse response of the ocean. When this impulse response is convolved with a source function, a waveform envelope prediction is made that can be compared with recorded data. In this paper we present the model and a few applications of the model using data recorded from earthquakes and explosions in the Atlantic and Indian Oceans. These examples illustrate the use of the model and initial steps toward model calibration.

1.
Angell
,
J.
,
Farrell
,
T.
, and
Pulli
,
J.
(
1998
). “
Characterization of reflected hydroacoustic signals
,”
Proceedings of the 20th Annual Seismic Research Symposium
, Department of Defense, NTP, pp.
650
659
.
2.
Chapman
,
R.
(
2004
). “
Directionality of acoustic T-phase signals from shallow underwater earthquakes
,”
J. Acoust. Soc. Am.
115
,
2445
.
4.
Comprehensive Nuclear-Test-Ban-Treaty
(
1996
). United Nations, Annex 1, pp.
180
181
.
5.
GDEM, Database Description for the Master Generalized Digital Environment Model (GDEM) Version 5.0
(
1995
). OAML DBD-20F, Naval Oceanographic Office, Stennis Space Center MS.
6.
Hanson
,
J.
(
2001
). “
Initial analysis of data from the New Diego Garcia Hydroacoustic Station
,”
23rd Seismic Research Review
, Jackson Hole, WY, Department of Energy, LA-UR-01-4454, Vol.
II
, pp.
12
22
.
7.
Hanson
,
J.
,
Bowman
,
R.
, and
Beall
,
G.
(
2002
). “
An advanced concept demonstration for monitoring the Indian Ocean
,”
24th Seismic Research Review
, Ponte Vedra Beach, FL, Department of Energy, LA-UR-02-5048, pp.
632
642
.
22.
Harben
,
P.
, and
Boro
,
C.
(
2001
). “
Implosion Source Development and Diego Garcia Reflections
,”
23rd Seismic Research Review
, Jackson Hole, WY, Department of Energy, LA-UR-01–4454, Vol.
II
, pp.
23
31
.
8.
Heaney
,
K.
,
Kuperman
,
W.
, and
McDonald
,
B.
(
1991
). “
Perth–Bermuda sound propagation (1960): Adiabatic mode interpretations
,”
J. Acoust. Soc. Am.
90
,
2586
2594
.
9.
Kibblewhite
,
A. C.
, and
Denham
,
R. N.
(
1969
). “
Hydroacoustic signals from the CHASE V explosion
,”
J. Acoust. Soc. Am.
45
,
944
956
.
10.
Lawrence
,
M.
,
Galindo
,
M.
,
Grenard
,
P.
, and
Newton
,
J.
(
2001
). “
Hydroacoustic monitoring system for the Comprehensive Nuclear Test Ban Treaty
,”
Kerntechnik
66
,
90
95
.
11.
Northrop
,
J.
(
1968
). “
Submarine topographic echoes from Chase V
,”
J. Geophys. Res.
73
,
3909
3916
.
12.
Pulli
,
J. J.
,
Farrell
,
T.
, and
Gibson
,
R.
(
1999
). “
Characterization and utilization of hydroacoustic signals reflected from continents and bathymetric features
,”
21st Seismic Research Symposium
, Las Vegas, NV, Department of Defense, LA-UR-99-4700.
13.
Pulli
,
J. J.
,
Upton
,
Z.
,
Gibson
,
R.
, and
Farrell
,
T.
(
2000
). “
Modeling long-range hydroacoustic reflections in the Atlantic and Pacific Oceans
,”
Proceedings of the 22nd Seismic Research Symposium
, New Orleans, LA, Defense Threat Reduction Agency, OMB No. 0704-0188. Vol.
III
, pp.
75
84
.
24.
Shurbet
,
D.
, and
Ewing
,
M.
(
1957
). “
T-phases at Bermuda and transformation of elastic waves
,”
Bull. Seismol. Soc. Am.
47
,
251
262
.
16.
Teague
,
W. J.
,
Carron
,
M. J.
, and
Hogan
,
P. J.
(
1990
). “
A comparison between the generalized digital environment model and levitus climatologies
,”
J. Geophys. Res.
95
,
7167
7183
.
17.
Tolstoy
,
M.
, and
Bohnenstiehl
,
D. R.
(
2002
). “
Analysis of hydroacoustic signals in the Indian Ocean
,
24th Seismic Research Review
, Ponte Vedra Beach, FL, Department of Energy, LA-UR-02-5048, pp.
666
675
.
18.
Upton
,
Z. M.
, and
Pulli
,
J.
(
2002
). “
Localization of sub-sea earthquakes using hydroacoustic reflections and matched-field processing
,”
24th Seismic Research Review
, Ponte Vedra Beach, FL, Department of Energy, LA-UR-02-5048, pp.
676
685
.
19.
Upton
,
Z.
,
Bhattacharyya
,
J.
,
Pulli
,
J.
,
Shah
,
S.
, and
Collins
,
M.
(
2005a
). “
Improving the physical understanding of hydroacoustic blockage: Statistical and model based studies
,”
27th Seismic Research Review
, Rancho Mirage, CA, Department of Energy, LA-UR-05-6407, pp.
749
758
.
20.
Upton
,
Z.
,
Farrell
,
T.
,
LePage
,
K.
,
Barklay
,
C.
,
Angell
,
J.
, and
Barger
,
M.
(
2005b
). “
HydroCAM Horizontal Path Prediction: The Globeray Model
,” BBN Technical Memorandum W-2060, BBN Technologies, 1300 N. 17th Street, Arlington, VA 22209.
21.
Urick
,
R.
(
1983
).
Principles of Underwater Sound
, 3rd ed. (
McGraw-Hill
, New York), pp.
159
164
.
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