goal: learn about potential, principles and format : lecture, sometimes followed by exercise. course...
TRANSCRIPT
Goal:Goal: Learn about potential, principles andLearn about potential, principles and
FormatFormat: Lecture, sometimes : Lecture, sometimes followed by exercise. Course project. followed by exercise. Course project.
. .
TopicsTopics: Deterministic interferometry, stochastic : Deterministic interferometry, stochastic interferometry, 3x3 classification matrix, interferometry, 3x3 classification matrix, reciprocity theorems, applications to VSP, reciprocity theorems, applications to VSP, SSP, OBS, and Xwell data. SSP, OBS, and Xwell data.
Seismic Interferometry CourseSeismic Interferometry Course
(Schuster, Cambridge Press) (Schuster, Cambridge Press) algorithms of seismic interferometryalgorithms of seismic interferometry
Seismic Interferometry:Seismic Interferometry: Instead of using just primaryInstead of using just primary
arrivals, you also use the multiples for a wider viewarrivals, you also use the multiples for a wider view
Overview of Seismic Interferometry Overview of Seismic Interferometry and Applications in Explorationand Applications in Exploration
Gerard SchusterGerard Schuster
KAUST & University of UtahKAUST & University of Utah
OutlineOutline•What is Seismic Interferometry?What is Seismic Interferometry?
•ApplicationsApplications
•ConclusionsConclusions
•VSP->SSP (surface seismic profile)VSP->SSP (surface seismic profile)•VSP->SWP (single well profile)VSP->SWP (single well profile)•SSP->SSP SSP->SSP
SELECTIVE HISTORY SEISMIC INTERFEROMETRYSELECTIVE HISTORY SEISMIC INTERFEROMETRY
1968 1968 Claerbout V(z)+passiveClaerbout V(z)+passive
1980s1980s Cole+Claerbout V(x,y,z)+passive?Cole+Claerbout V(x,y,z)+passive?
1990s1990s Scherbaum earthquake V(z)+passiveScherbaum earthquake V(z)+passive
20012001 Utah: Stationary Phase Theory, SSP, and VSPUtah: Stationary Phase Theory, SSP, and VSP
Seismic Interferometric imaging, deterministicSeismic Interferometric imaging, deterministic
2002-042002-04 Wapenaar Recip. Thm. Correlation TypeWapenaar Recip. Thm. Correlation Type
Shell Virtual Sources:Calvert+BakulinShell Virtual Sources:Calvert+Bakulin
Snieder Stationary Phase RedatumingSnieder Stationary Phase Redatuming
Gerstoft + others Surface Wave InterferometryGerstoft + others Surface Wave Interferometry
19991999 Rickett+Claerbout V(z) HelioseismologyRickett+Claerbout V(z) HelioseismologyDaylight ImagingDaylight Imaging , passive, passive
1970s 1970s Berryhill model-based redatumBerryhill model-based redatum
redatum
SELECTIVE HISTORY SEISMIC INTERFEROMETRYSELECTIVE HISTORY SEISMIC INTERFEROMETRY
redatum
Surface wavesShapiro, Derode, Larose, Dong, Shapiro, Derode, Larose, Dong,
Xue, Halliday, Curtis,Xue, Halliday, Curtis,
Van Mannen, Robertsson,Van Mannen, Robertsson,
Gerstoft,Gerstoft, Sabra, Kepler, Roux, Sabra, Kepler, Roux,
He, Ritzwoller, Campillo etcHe, Ritzwoller, Campillo etcInterpolationSheng, Curry, Berkhout, Wang,Sheng, Curry, Berkhout, Wang,
Dong, Hanafy, Cao, etcDong, Hanafy, Cao, etc
Extrapolation
Dong, Hanafy, Cao, etcDong, Hanafy, Cao, etc
Theory: Acoustic, EM, Elastic, Potential
Fink, Wapenaar, Snieder, Papanicolaou, Blomgren,Fink, Wapenaar, Snieder, Papanicolaou, Blomgren,
Slob, Thorbeck, van der Neut etcSlob, Thorbeck, van der Neut etc
Refractions
Boise State Univ, DongBoise State Univ, Dong
Passive Reservoir
Shell, Draganov, Shell, Draganov,
Wapenaar, Snieder, Polleto Wapenaar, Snieder, Polleto
Miranda, etc Miranda, etc
Exploration
Curry, Guitton, Shragg, Yu,Curry, Guitton, Shragg, Yu,
ArtmanArtman
Yu, Calvert, Bakulin,Yu, Calvert, Bakulin, He, He,
Jiang, Hornby, Xiao, Willis, Lu,Jiang, Hornby, Xiao, Willis, Lu,
Toksoz, Campman etcToksoz, Campman etc
VSP
Model TankScales, Malcolm etcScales, Malcolm etc
Volcanoes+Coda
Snieder, Scales, Gret et alSnieder, Scales, Gret et al
Engineering Xwell
Minato, Onishi, Matsuoka etcMinato, Onishi, Matsuoka etc
Nowack, Sheng, Curtis etcNowack, Sheng, Curtis etc
Earthquakes
EMSlob, Wapenaar, SniederSlob, Wapenaar, Snieder
What is Seismic Interferometry?What is Seismic Interferometry?Answer: Redatums data byAnswer: Redatums data by correlationcorrelation of trace pairs andof trace pairs and
stacking the result for different shot positions stacking the result for different shot positions
A
G(G(BB||xx)) G(G(BB||xx))** = G(= G(BB||BB)) Point Source Response
with src at B and rec at B
Assume aAssume a
VSP experimentVSP experiment
directF.S. multiple
iiee
xxBB+ + BBzz zzB B iiee
xxBB iiee
BBzz zzBB=
VSP => SSPVSP => SSP
BB
zz zz
Phase of CommonPhase of Common
Raypath CancelsRaypath Cancels
virtual
primary
BB
xx
zz
virtual
source
correlationcorrelation
•No need to know src. locationNo need to know src. location
•No need to know src excitation timeNo need to know src excitation time
stackingstacking
•Redatum source closer to targetRedatum source closer to target
s
A
G(G(BB||xx)) G(G(BB||xx))** = G(= G(BB||BB)) Point Source Response
with src at B and rec at B
iiee
xxBB+ + BBzz zzB B iiee
xxBB iiee
BBzz zzBB=
zz zz
Phase of CommonPhase of Common
Raypath CancelsRaypath Cancelsxx
zz
x
xx
~~~~
•No need to know src. locationNo need to know src. location
•No need to know src excitation timeNo need to know src excitation time
•Redatum source closer to targetRedatum source closer to target
Answer: Redatums data byAnswer: Redatums data by correlationcorrelation of trace pairs andof trace pairs and
stacking the result for different shot positions stacking the result for different shot positions
correlationcorrelation
stackingstacking
What is Seismic Interferometry?What is Seismic Interferometry?
Reciprocity Correlation EquationReciprocity Correlation Equation2D Reflection Data2D Reflection Data
Phase of Common Raypath Cancels
xx xx
AAAABB
VSPVSPVSPVSP SSPSSP
BB AA
Old Multiples Become
New Primaries!
x
= G(= G(AA||BB)) G(G(x|x|BB)*)* G(G(x|x|AA)) k ~~~~
•No need to know VSP rec location at x
•No need to know receiver statics
Reciprocity Correlation EquationReciprocity Correlation Equation2D Reflection Data2D Reflection Data
x
= G(= G(AA||BB)) G(G(x|x|BB)*)* G(G(x|x|AA)) k
xx xx
AAAABB AABB
Old Multiples Become
New Primaries!
{ }{ }G(G(AA||xx))G(G(BB||xx)) G(G(BB||xx)) - G(- G(AA||xx)) d x
2= = G(G(AA||BB) - ) - G(G(BB||AA))n* * *
SS wellwell
(Wapenaar, 2004)(Wapenaar, 2004)
1-way+ far-field approx.1-way+ far-field approx.
Problems: FiniteProblems: Finite source aperturesource aperture
No attenuationNo attenuationDeghostfilt.,Deghostfilt., U & D separationU & D separation
Muting, Least squares or MDDMuting, Least squares or MDD
Atten. CompensationAtten. Compensation
Finite aperture leads to incomplete G(B|A)
Prediction Multiple by Convolution (SRME)Prediction Multiple by Convolution (SRME)
Prediction Primaries by CrosscorrelationPrediction Primaries by Crosscorrelation
(Crosscorrelation migration interferometry)(Crosscorrelation migration interferometry)
**
BB CCAA BB CC AA BB
50005000
130001300000 5600056000X (ft)X (ft)
De
pth
(ft)D
ep
th (ft)
VSP Multiple (12 receivers 13 kft @ VSP Multiple (12 receivers 13 kft @ 30 ft spacing; 500 shots) 30 ft spacing; 500 shots)
TLE, Jiang et al., 2005TLE, Jiang et al., 2005
50005000
130001300000 5600056000X (ft)X (ft)
De
pth
(ft)D
ep
th (ft)
Surface SeismicSurface Seismic
TLE, Jiang et al., 2005TLE, Jiang et al., 2005
50005000
130001300000 5600056000X (ft)X (ft)
De
pth
(ft)D
ep
th (ft)
VSP Multiple (12 receivers 13 kft @ VSP Multiple (12 receivers 13 kft @ 30 ft spacing; 500 shots) 30 ft spacing; 500 shots)
TLE, Jiang et al., 2005TLE, Jiang et al., 2005
Instead of using just primaryInstead of using just primary
arrivals, you also use the multiples for a wider/partialarrivals, you also use the multiples for a wider/partial visionvision
Small vs Huge IlluminationSmall vs Huge Illumination
Primary reflectionsPrimary reflections Multiple reflectionsMultiple reflections
Standard VSP ImagingStandard VSP Imaging Interferometric VSP ImagingInterferometric VSP Imaging
Standard VSP vs Interferometric VSP ImagingStandard VSP vs Interferometric VSP Imaging
Stellar InterferometryStellar InterferometryAn astronomical interferometer is an array of telescopes or mirror An astronomical interferometer is an array of telescopes or mirror
segments acting together to probe structures with higher resolution. segments acting together to probe structures with higher resolution.
stellar interferometry, a team of French astronomers has captured one of the sharpest color images ever made. They observed the star T Leporis stellar interferometry, a team of French astronomers has captured one of the sharpest color images ever made. They observed the star T Leporis
with the European Southern Observatory's with the European Southern Observatory's Very Large Telescope Interferometer (VLTI; Cerro Paranal, Chile), which emulates a virtual telescope (VLTI; Cerro Paranal, Chile), which emulates a virtual telescope
about 100 meters across, and which revealed a spherical molecular shell around the aged star. about 100 meters across, and which revealed a spherical molecular shell around the aged star.
3x3 Classification Matrix3x3 Classification Matrix
SSPSSP VSPVSP SWPSWP
VSPVSP
SSPSSP
SWPSWP
SSPSSP SSPSSP SSPSSP SSPSSPVSPVSP SWPSWP
VSPVSP VSPVSP VSPVSP
SWPSWP SWPSWP SWPSWP
VSPVSP
SWPSWP
SWPSWP
VSPVSP
SSPSSP
SSPSSP
inout
SummarySummary•Seismic InterferometrySeismic Interferometry: :
x Im[G(Im[G(AA||BB)])] G(G(x|x|BB)*)* G(G(x|x|AA)) ~~~~
AA BB
x
G(G(AA||xx)) G(G(BB||xx))
imaginary
k
AA BB
x
G(G(AA||BB))
•Merits:Merits: Eliminates need for src location, excitation time, some statics. Eliminates need for src location, excitation time, some statics. Moves rec./srcs closer to target , no velocity model needed (unlike Moves rec./srcs closer to target , no velocity model needed (unlike Berryhill).Berryhill).
•Challenges:Challenges: Finite aperture and noise, attenuation, acoustic & farfield Finite aperture and noise, attenuation, acoustic & farfield approximations , amplitude fidelityapproximations , amplitude fidelity
•Killer Apps in Earthquake:Killer Apps in Earthquake: Surface wave interferometry Surface wave interferometry
•Killer Apps in Exploration:Killer Apps in Exploration: Passive reservoir monitoring? OBS? EM? VSP Passive reservoir monitoring? OBS? EM? VSP
OutlineOutline
•What is Seismic Interferometry?What is Seismic Interferometry?
•Reciprocity Equation Correlation TypeReciprocity Equation Correlation Type
•Classification MatrixClassification Matrix
•ApplicationsApplications
•ConclusionsConclusions
•Background for Non-geo typesBackground for Non-geo types
Reciprocity Eqn. of Correlation TypeReciprocity Eqn. of Correlation Type1. Helmholtz Eqns: 1. Helmholtz Eqns:
2+ k
2[ ] G(A|x) =- (x-A);
2+ k
2[ ] P(B|x) =- (x-B) **
**
2 2+ k[ ] G(A|x) =- (x-A) P(B|x) P(B|x)
2 2+ k[ ] P(B|x) =- (x-B) G(A|x) G(A|x)
** **
G(A|x)P(B|x) P(B|x) - G(A|x)2
= (B-x)G(A|x) - (A-x)P(B|x) 2
**** **
2. Multiply by 2. Multiply by G(A|x)G(A|x) and and P(B|x)P(B|x) and subtract and subtract**
G(A|x)
A A B B
Free surface
P(B|x)
xx
G(A|x) = G(A|x) = P(B|x) P(B|x)P(B|x) G(A|x)G(A|x)2
{ } - - P(B|P(B|xx)) G(A|x)G(A|x)****** [ ]
P(B|P(B|xx)) = = G(A|x) G(A|x) G(A|x) P(BP(B|x|x))2
- G(A|x) - G(A|x) P(BP(B|x|x))[[ ]] ****** [ ]
Reciprocity Eqn. of Correlation TypeReciprocity Eqn. of Correlation Type1. Helmholtz Eqns: 1. Helmholtz Eqns:
2+ k
2[ ] G(A|x) =- (x-A);
2+ k
2[ ] P(B|x) =- (x-B) **
**
2 2+ k[ ] G(A|x) =- (x-A) P(B|x) P(B|x)
2 2+ k[ ] P(B|x) =- (x-B) G(A|x) G(A|x)
** **
G(A|x)P(B|x) P(B|x) - G(A|x)2
= (B-x)G(A|x) - (A-x)P(B|x) 2
**** **
2. Multiply by 2. Multiply by G(A|x)G(A|x) and and P(B|x)P(B|x) and subtract and subtract**
G(A|x) = G(A|x) = P(B|x) P(B|x)P(B|x) G(A|x)G(A|x)2
{ } - - P(B|P(B|xx)) G(A|x)G(A|x)******
P(B|P(B|xx)) = = G(A|x) G(A|x) G(A|x) P(BP(B|x|x))2
- G(A|x) - G(A|x) P(BP(B|x|x))[[ ]] ******
G(A|x)P(B|x) P(B|x) - G(A|x){ { } } = (B-x)G(A|x) - (A-x)P(B|x) ******
G(A|x)
A A B B
Free surface
P(B|x)
xx
Reciprocity Eqn. of Correlation TypeReciprocity Eqn. of Correlation Type3. Integrate over a volume3. Integrate over a volume
4. Gauss’s Theorem4. Gauss’s Theorem
Source lineSource line
G(A|x)P(B|x) P(B|x) - G(A|x) d x3
= G(A|B) - P(B|A){ }{ } ******
G(A|x)P(B|x) P(B|x) - G(A|x) d x2
= G(A|B) - P(B|A){ }{ } n** ** **
G(A|B) G(A|B)
Integration at infinity vanishesIntegration at infinity vanishesA A B B
Free surface
xx
Reciprocity Eqn. of Correlation TypeReciprocity Eqn. of Correlation Type3. Integrate over a volume3. Integrate over a volume
4. Gauss’s Theorem4. Gauss’s Theorem
Source lineSource line
G(A|x)P(B|x) P(B|x) - G(A|x) d x3
= G(A|B) - P(B|A){ }{ } ******
G(A|x)G(B|x) G(B|x) - G(A|x) d x2
= G(A|B) - G(B|A){ }{ }
n** ** **
G(A|B) G(A|B)
Integration at infinity vanishesIntegration at infinity vanishesA A B B
Free surface
xx
Relationship between reciprocal Green’s functionsRelationship between reciprocal Green’s functions
Reciprocity Eqn. of Correlation TypeReciprocity Eqn. of Correlation Type
Source lineSource line
G(A|x)G(B|x) G(B|x) - G(A|x) d x2
= G(A|B) - G(B|A){ }{ }
n** ** **= 2i Im[G(A|B)]= 2i Im[G(A|B)]
Recall Recall G(A|x ) =G(A|x ) =
|r||r|
iwr/ciwr/ceeiw/ciw/c
nn nn rr
G(BG(B|x|x )* )* = =|r||r|
-iwr/c-iwr/cee-iw/c-iw/c
nn nn rr
(1)(1)
(2a)(2a)
(2b)(2b)
Plug (2a) and (2b) into (1)Plug (2a) and (2b) into (1)
G(A|x )G(A|x )ikik
G(B|G(B|xx ) )**-ik-ik
Source lineSource line
G(A|x)G(B|x) d x2
= G(A|B) - G(B|A)r** **= 2i Im[G(A|B)]= 2i Im[G(A|B)] (3)(3)n2ik2ik
Neglect 1/rNeglect 1/r22
A XX
B
Far-Field Reciprocity Eqn. of Correlation TypeFar-Field Reciprocity Eqn. of Correlation Type
G(A|B) G(A|B)
A A B B
Free surface
xx
nn rr ~~~~ 11
Source lineSource line
G(A|x)G(B|x) d x2
= G(A|B) - G(B|A)r** **= = 2i Im[G(A| Im[G(A|BB)])] (3)(3)nkk
Source lineSource line
G(A|x)G(B|x) d x2
= G(A|B) - G(B|A)r** **= = 2i Im[G(A| Im[G(A|BB)])] (4)(4)nkk
AA
nn rr^̂ ^̂
Far-Field Reciprocity Eqn. of Correlation TypeFar-Field Reciprocity Eqn. of Correlation Type
nn rr ~~~~ 11
Source lineSource line
G(A|x)G(B|x) d x2
= G(A|B) - G(B|A)r** **= = 2i Im[G(A|B)] Im[G(A|B)] (3)(3)nkk
Source lineSource line
G(A|x)G(B|x) d x2
= G(A|B) - G(B|A)r** **= = 2i Im[G(A|B)] Im[G(A|B)] (4)(4)nkk
G(A|B) G(A|B)
A A B B
Free surface
xx
Source lineSource line
G(A|x)G(B|x) d x2
= G(A|B) - G(B|A)r** **= = 2i Im[G(A|B)] Im[G(A|B)] (4)(4)nkk
Far-Field Reciprocity Eqn. of Correlation TypeFar-Field Reciprocity Eqn. of Correlation Type
xx
B AB A
G(B|x)*G(B|x)*
xx
B AB A
G(A|x)G(A|x)
xx
B AB A
G(A|B)G(A|B)
Source redatumed from x to BSource redatumed from x to B
Virtual sourceVirtual source
OutlineOutline•What is Seismic Interferometry?What is Seismic Interferometry?
•ApplicationsApplications
•ConclusionsConclusions
•VSP->SSP (surface seismic profile)VSP->SSP (surface seismic profile)•VSP->SWP (single well profile)VSP->SWP (single well profile)•SSP->SSP SSP->SSP
ImplementationImplementation
x
= Im[G(= Im[G(AA||BB)])] G(G(AA||xx)*)* G(G(BB||xx))kk
AA
xx
BBAA
xx
BB AA
xx
BB
VSP VSP SSPVSP VSP SSP
1. FK Filter up and downgoing waves1. FK Filter up and downgoing waves
2. Correlation: 2. Correlation: (A,B,x) = (A,B,x) = G(G(AA||xx)*)* G(G(BB||xx))
3. Summation: 3. Summation: x
= Im[G(= Im[G(AA||BB)])] kk (A,B,x) (A,B,x)
4. Migration:4. Migration: M(x) = M(x) = Mig(Mig(G(G(AA|B|B))))
Challenge: Finite Receiver Aperture = Partial ReconstructionChallenge: Finite Receiver Aperture = Partial Reconstruction
VSP Multiples MigrationVSP Multiples Migration
( CourtesyCourtesy of P/GSI: ~¼ million traces, ~3 GB memory, ~4 hours on a PC )
Stack of 6 receiver gathersStack of 6 receiver gathers
(He, 2006)(He, 2006)
BP 3D VSP Survey Geometry (36 recs)BP 3D VSP Survey Geometry (36 recs)~ 11 km~ 11 km
3 km3 km
1.6 km1.6 km
4.0 km4.0 km
(He et al., 2007)(He et al., 2007)
VSP->SSP SummaryVSP->SSP Summary
Key Point #1: Every Bounce Pt on Surface Acts a New Virtual SourceKey Point #1: Every Bounce Pt on Surface Acts a New Virtual Source
Key Point #2: Kills Receiver StaticsKey Point #2: Kills Receiver Statics
Key Point #3: Redatuming = Huge Increase Illumination areaKey Point #3: Redatuming = Huge Increase Illumination area
x
= Im[G(= Im[G(AA||BB)])] G(G(AA||xx)*)* G(G(BB||xx))kk
AA
xx
BBAA
xx
BB AA
xx
BB
VSP VSP SSPVSP VSP SSP
Key Point #4: Liabilities: Finite Aperture noise, attenuation, loss amplitudes fidelityKey Point #4: Liabilities: Finite Aperture noise, attenuation, loss amplitudes fidelity
OutlineOutline•What is Seismic Interferometry?What is Seismic Interferometry?
•ApplicationsApplications
•ConclusionsConclusions
•VSP->SSP (surface seismic profile)VSP->SSP (surface seismic profile)•VSP->SWP (single well profile)VSP->SWP (single well profile)•SSP->SSP SSP->SSP
Problem:Problem: Overburden+statics defocus VSP migration Overburden+statics defocus VSP migration
Redatum sources below overburdenRedatum sources below overburden
Local VSP migrationLocal VSP migration
Solution:Solution: VSP -> SWP Transform (Calvert, Bakulin) VSP -> SWP Transform (Calvert, Bakulin)
MotivationMotivation
VSPVSPVSPVSP SWPSWP
VSP GeometryVSP Geometry
Offset (m)Offset (m)00 10001000
DepthDepth (m)(m)
15001500
35003500Time (s)Time (s)
00
33
Reflection Reflection wavefieldwavefield
(He , 2006)(He , 2006)
VSP GeometryVSP Geometry
Offset (m)Offset (m)00 10001000
DepthDepth (m)(m)
15001500
35003500
(He , 2006)(He , 2006)
Time (s)Time (s)
00
33
Reflection Reflection wavefieldwavefield
superresolutionsuperresolution
China
VSP Salt Flank Imaging VSP Salt Flank Imaging (Hornby & Yu, 2006)(Hornby & Yu, 2006)
? 98 geophones
120 shots
Overburden
Poor image of flank by standard migrationPoor image of flank by standard migration
VSP->SWP SummaryVSP->SWP Summary
3. Kills Source Statics and no need to know src location or excitation time3. Kills Source Statics and no need to know src location or excitation time
1. Redatum sources below overburden1. Redatum sources below overburden
2. Local VSP migration2. Local VSP migration
4. Super-resolution4. Super-resolution
5. Instead of redatuming receivers to surface, we5. Instead of redatuming receivers to surface, we
redatum sources to depth.redatum sources to depth.
OutlineOutline•What is Seismic Interferometry?What is Seismic Interferometry?
•ApplicationsApplications
•ConclusionsConclusions
•VSP->SSP (surface seismic profile)VSP->SSP (surface seismic profile)•VSP->SWP (single well profile)VSP->SWP (single well profile)•SSP->SSP SSP->SSP
xx BBAA
Surface Wave InterferometrySurface Wave Interferometry
G(G(AA||xx)*)* G(G(BB||xx))
xx BBAA
G(G(BB||AA))
AA
Surface Wave InterferometrySurface Wave Interferometry
G(G(AA||xx)* G()* G(BB||xx) = G() = G(BB||AA))
BB
xx
Shear velocityShear velocity
AA
Surface Wave InterferometrySurface Wave Interferometry
G(G(AA||xx)* G()* G(BB||xx) = G() = G(BB||AA))
BB
xx
x
Yao (2009)Yao (2009)
S-velocity distribution, surface wave predic.+eliminationS-velocity distribution, surface wave predic.+elimination
3x3 Classification Matrix3x3 Classification Matrix
SSPSSP VSPVSP SWPSWP
VSPVSP
SSPSSP
SWPSWP
SSPSSP SSPSSP SSPSSP SSPSSPVSPVSP SWPSWP
VSPVSP VSPVSP VSPVSP
SWPSWP SWPSWP SWPSWP
VSPVSP
SWPSWP
SWPSWP
VSPVSP
SSPSSP
SSPSSP
inout
SummarySummary•Seismic InterferometrySeismic Interferometry: :
x Im[G(Im[G(AA||BB)])] G(G(x|x|BB)*)* G(G(x|x|AA)) ~~~~
k
AA BB
x
G(G(AA||BB))AA BB
x
G(G(AA||xx)) G(G(BB||xx))•Merits:Merits: Eliminates need for src location, excitation time, some statics. Eliminates need for src location, excitation time, some statics. Moves rec./srcs closer to target , no velocity model needed (unlike Moves rec./srcs closer to target , no velocity model needed (unlike Berryhill).Berryhill).
•Challenges:Challenges: Finite aperture and noise, attenuation, acoustic & farfield Finite aperture and noise, attenuation, acoustic & farfield approximations , amplitude fidelityapproximations , amplitude fidelity
•Killer Apps in Earthquake:Killer Apps in Earthquake: Surface wave interferometry Surface wave interferometry
•Killer Apps in Exploration:Killer Apps in Exploration: Passive reservoir monitoring? OBS? EM? VSP Passive reservoir monitoring? OBS? EM? VSP
ThanksThanks
•UTAM sponsorsUTAM sponsors
•Min Zhou, Chaiwoot Boonyasiriwat, Ge ZhanMin Zhou, Chaiwoot Boonyasiriwat, Ge Zhan
OutlineOutline
•What is Seismic Interferometry?What is Seismic Interferometry?
•Reciprocity Equation Correlation TypeReciprocity Equation Correlation Type
•Classification MatrixClassification Matrix
•ApplicationsApplications
•ConclusionsConclusions
•Background for Non-geo typesBackground for Non-geo types
Survey Goal: GetSurvey Goal: Get d d fromfrom dd Geologist Goal: GetGeologist Goal: Get mm fromfrom d d
d(g,t)d(g,t)
gg
tt
m(x,z)m(x,z)
LLmm==dd m m = [L L] L = [L L] L d ~ d ~ LL d dTT TT TT-1-1
Model basedModel based
Data basedData based
Source lineSource line
G(A|x)G(B|x) d x2
= G(A|B) - G(B|A)r** **= = 2i Im[G(A|B)] Im[G(A|B)] (4)(4)nkk
Far-Field Reciprocity Eqn. of Correlation TypeFar-Field Reciprocity Eqn. of Correlation Type
Source redatumed from x to BSource redatumed from x to B
xx
B AB A
G(B|x)*G(B|x)*
xx
B AB A
G(A|x)G(A|x)
xx
B AB A
G(A|B)G(A|B)Recovering the Green’s function
OutlineOutline
•What is Seismic Interferometry?What is Seismic Interferometry?
•Reciprocity Equation Correlation TypeReciprocity Equation Correlation Type
•Classification MatrixClassification Matrix
•ApplicationsApplications
•ConclusionsConclusions
•Background for Non-geo typesBackground for Non-geo types