Airborne Magnetic Measurements Associated with SW06 Experiment
Preliminary Geoacoustic Inversion Results from SW06 Data
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eliminary Geoacoustic Inversion Result from SW06 Data Ross Chapman ONR Shallow Water Experiment 06 Workshop January, 30-31, 2007 San Diego, CA University of Victoria, BC, Canada
description
Preliminary Geoacoustic Inversion Results from SW06 Data. Ross Chapman. University of Victoria, BC, Canada. ONR Shallow Water Experiment 06 Workshop January, 30-31, 2007 San Diego, CA. Low Frequency Geoacoustics (Knorr: Aug 23 – Sept 06) Bill Hodgkiss, Peter Gerstoft, Chenfen Huang (MPL) - PowerPoint PPT Presentation
Transcript of Preliminary Geoacoustic Inversion Results from SW06 Data
Preliminary Geoacoustic Inversion Results from SW06 Data
Ross Chapman
ONR Shallow Water Experiment 06 WorkshopJanuary, 30-31, 2007 San Diego, CA
University of Victoria, BC, Canada
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Low Frequency Geoacoustics (Knorr: Aug 23 – Sept 06)
- Bill Hodgkiss, Peter Gerstoft, Chenfen Huang (MPL)
- David Knobles et al (ARL)
- Ross Chapman, Yongmin Jiang, (UVic)
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Data sets used (at VLA1):• Low frequency tonals for 3 ranges along ‘DJ’ track• Chirps at fixed range
Objectives:• Geoacoustic model for common site
• Broad frequency band• Well surveyed range dependence
Approaches:• MFI for tonal signals
• single layer geoacoustic model• Reflection coefficient inversion of fixed range chirp data
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Example of matched field inversion result – parameter uncertainty estimates at WP21 (~ 1km)
75 80 85
WD: 79.466(m)
20 40 60
H: 44.168(m)
1400 1600 1800
cp1: 1574.828(m/s)
1600 1800 2000 2200 2400
cpb: 1648.879(m/s)
0.2 0.4 0.6 0.8
p1: 0.939(dB/m/kHz)
0.2 0.4 0.6 0.8
pb: 0.252(dB/m/kHz)
1.5 2 2.5
1: 1.933(g/cm3)
2 2.5 3
b: 2.532(g/cm3)
25 30 35
SD: 30.284(m)
0.5 1 1.5
Range: 1.164(km)
8 10 12 14
rdvb: 12.588(m)
1 1.5 2
fexp: 1.096
0 5 10
tilt: 1.207( )
0 50 100 150
Steer: 98.379( )
File: jd239lm00137; Date: 26-Jan-2007
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Example of data processing for reflectivity coefficient inversion – Fixed range high frequency chirps
• Sea floor & subbottom reflection at VLA1 site
• Sound speed and attenuation from 2000 ~ 4000 Hz
• Sound speed ~ 1580 m/s
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
• Some problems with the data:• MFI: no information in some tonal frequencies• Significant variation in signal level• Significant variation in SSP• Array geometry: hydrophone depths uncertain?
• What other information do we need?• Chirp sonar track over DJ line; geoprobe data• Swell and wave direction & height• Source levels for LF and MF sound sources• ARL acoustic data from SWAMIs
• Preliminary low frequency geoacoustic model for ‘DJ’ track• sea floor sediment parameters over range dependent track• sediment sound speed: ~1600 m/s (50 – 900 Hz)
Collaborations for geoacoustics:- Geoacoustic models for broad frequency band for DJ track and Moray/VLA site- SWAMI site data-
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Collaborations for geoacoustics:- Geoacoustic models for broad frequency band for DJ track and Moray/VLA site:
MPL (LF < 4500 Hz) and APL (2 – 20 kHz)
- SWAMI site data: ARL- long and short range geoacoustic inversion at sandy site- expect less variation in SSP- LF and MF data (chirps)
- Experimental benchmark data set for inversion methods?
- Target a JASAEL collection of preliminary results (2007)?
- Hurricane Ernesto Noise data: SWAMIs
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Discussion Slides
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
final energy of each frequency in optimization: 0.2338038 0.00363505 ( 53Hz) 0.21442491(103Hz) 0.56934798(203Hz) 0.40013963(253Hz) 0.57140428 (303Hz) 0.37056041(403Hz) 0.35731304(503Hz) 0.66464043(703Hz)
Energy Function:
F
F
ff mBmE
1
)()(
2)(
)(ˆ)()ˆ()(
mp
mpRmpRTrmB
f
fffff
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.6419
File: jd239l00101; Date: 16-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (0.6500km ,71.5m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
700.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
WD=79.5, Rdvb = 8.2m
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.6732
File: jd239l00101; Date: 16-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (0.6400km ,71.5m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
70
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
WD=79.5m, Rdvb=11.8m
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.5367
File: jd239l00101; Date: 16-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (1.1200km ,29.2m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
70
0.2
0.25
0.3
0.35
0.4
0.45
0.5
WD=78.8, rdvb =11.8m, 8fres
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.4593
File: jd239l00101; Date: 16-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (0.6800km ,73.3m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
70
0.2
0.25
0.3
0.35
0.4
WD=78.8, rdvb =8.2m, 8fres
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Range(km)
Dep
th(m
) Maximum value of bartlett: 0.4350
File: jd239l00101; Date: 17-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (0.6200km ,69.3m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
70
0.15
0.2
0.25
0.3
0.35
0.4
WD=78.8, rdvb =9.05m, 8fres
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.4666
File: jd239l00101; Date: 18-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (0.6900km ,72.5m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
70
0.2
0.25
0.3
0.35
0.4
WD=78.8, rdvb =8.55m, 8fres
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.6832
File: jd239l00101; Date: 16-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (0.6200km ,70.9m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
70
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
WD=78.8, rdvb =11.8m, wp21 ssp
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.6662
File: jd239l00101; Date: 16-Jan-2007--"+" TRUE (0.9800km ,30.0m); "o" ESTIMATED (0.6200km ,70.8m); x=0.0100km, y= 0.8m
0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
0
10
20
30
40
50
60
70
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
WD=78.8, rdvb =11.8m, wp22 ssp
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
WD=78.8, rdvb =11.8m, WP22 WD=78.8, rdvb =8.2m, WP22
WD=81.0, rdvb =11.8m, WP23 WD=81.0, rdvb =8.2m, WP23
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.5053
File: jd239l05401; Date: 18-Jan-2007--"+" TRUE (2.9800km ,30.0m); "o" ESTIMATED (2.9800km ,29.9m); x=0.0100km, y= 0.8m
2.5 2.6 2.7 2.8 2.9 3 3.1 3.2 3.3 3.4 3.5
0
10
20
30
40
50
60
70 0.2
0.25
0.3
0.35
0.4
0.45
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.4988
File: jd239l05401; Date: 18-Jan-2007--"+" TRUE (2.9800km ,30.0m); "o" ESTIMATED (2.9800km ,29.2m); x=0.0100km, y= 0.8m
2.5 2.6 2.7 2.8 2.9 3 3.1 3.2 3.3 3.4 3.5
0
10
20
30
40
50
60
70 0.2
0.25
0.3
0.35
0.4
0.45
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.4898
File: jd239l09601; Date: 18-Jan-2007--"+" TRUE (4.9800km ,30.0m); "o" ESTIMATED (5.0500km ,32.8m); x=0.0100km, y= 0.8m
4.5 4.6 4.7 4.8 4.9 5 5.1 5.2 5.3 5.4 5.5
0
10
20
30
40
50
60
70
80
0.2
0.25
0.3
0.35
0.4
0.45
Range(km)
Dep
th(m
)
Maximum value of bartlett: 0.5194
File: jd239l09601; Date: 18-Jan-2007--"+" TRUE (4.9800km ,30.0m); "o" ESTIMATED (5.1500km ,29.6m); x=0.0100km, y= 0.8m
4.5 4.6 4.7 4.8 4.9 5 5.1 5.2 5.3 5.4 5.5
0
10
20
30
40
50
60
70
80
0.2
0.25
0.3
0.35
0.4
0.45
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Discussion:
75 80 85
WD: 78.4009(m)
20 40 60
H: 52.4378(m)
1400 1600 1800
cp1: 1611.5787(m/s)
2000 2500
cpb: 1988.2227(m/s)
0.5 1
p1: 0.5535(dB/m/kHz)
0.5 1
pb: 0.5103(dB/m/kHz)
1.5 2 2.5
1: 1.7968(g/cm 3)
2 2.5 3
b: 2.6831(g/cm 3)
25 30 35
SD: 30.6447(m)
0.5 1 1.5
Range: 1.0724(km)
8 10 12 14
rdvb: 12.2129(m)
1 1.5 2
fexp: 1.0645
0 5 10
tilt: 1.9609( )
0 100
Steer: 114.4619( )
File: wp21lm.dat; Date: 20-Jan-2007
Way Point 21(0.98km), LF(5mins) + MF(5mins) Tonal, 8 fres
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
75 80 85
WD: 78.6614(m)
20 40 60
H: 52.2724(m)
1400 1600 1800
cp1: 1652.5365(m/s)
2000 2500
cpb: 1889.8889(m/s)
0 0.5 1
p1: 0.9960(dB/m/kHz)
0.5 1
pb: 0.0107(dB/m/kHz)
1.5 2 2.5
1: 1.8669(g/cm 3)
2 2.5 3
b: 2.9973(g/cm 3)
20 30 40
SD: 31.3392(m)
2.5 3 3.5
Range: 3.0363(km)
10 15
rdvb: 12.0089(m)
1 2 3
fexp: 2.1332
0 5 10
tilt: 1.6897( )
0 100
Steer: 78.7805( )
File: wp22.dat; Date: 20-Jan-2007
Way Point 22(2.98km), LF(5mins) Tonal(53, 103 203, 253)Hz
ONR SW06 Workshop, January, 30-31, 2007 San Diego, CA
Way Point 23(4.98km), LF(5mins) Tonal(53, 103 203, 253)Hz
75 80 85
WD: 80.6887(m)
20 40 60
H: 61.2443(m)
1400 1600 1800
cp1: 1627.5771(m/s)
2000 2500
cpb: 1995.1620(m/s)
0 0.5 1
p1: 0.9977(dB/m/kHz)
0.5 1
pb: 0.0126(dB/m/kHz)
1.5 2 2.5
1: 2.0976(g/cm 3)
2 2.5 3
b: 2.6372(g/cm 3)
20 30 40
SD: 30.5472(m)
4.5 5 5.5
Range: 5.2361(km)
10 15
rdvb: 9.4056(m)
1 2 3
fexp: 1.4695
0 5 10
tilt: 3.6891( )
0 100
Steer: 126.3276( )
File: wp23.dat; Date: 20-Jan-2007
