Seismic Interferometry

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Seismic Interferometry
Gerard Schuster University of Utah
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Seismic Interferometry
Instead of using just primary arrivals, you also
use the multiples for a wider more complete view
Gerard Schuster University of Utah
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Overview of Seismic Interferomtery Short Course
Primary reflections
Multiple reflections
Small vs Huge Illumination
Instead of using just primary arrivals, you also
use the multiples for a wider vision
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Overview of Seismic Interferomtery Short Course
Local VSP migration
Redatum sources below overburden
Instead of using just primary arrivals, you also
use the multiples for a wider vision
clearer
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Overview of Seismic Interferomtery Short Course
Data Extrapolation
Instead of using just primary arrivals, you also
use the multiples for a wider vision
clearer
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Overview of Seismic Interferomtery Short Course
Hydrofrac location
Monitoring 4D
Instead of using just primary arrivals, you also
use the multiples for a wider vision
clearer
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Goal Learn Principles and Algorithms in
Seismic Interferometry
Format Mornings Lecture 50 minutes, followed
by exercise or MATLAB lab.
Format Afternoon MATLAB labsdiscussion.
Topics Deterministic interferometry, stochastic
interferometry, 3x3
classification matrix, reciprocity
theorems, applications to VSP,
SSP, OBS, and Xwell data.
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What is Seismic Interferometry?
Answer Correlation and summation of trace pairs
and stacking the result for different shot
positions

G(BB)

VSP gt SSP
Assume a VSP experiment
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What is Seismic Interferometry?
Answer Correlation and summation of trace pairs
and stacking the result for different shot
positions
-

G(BB)
VSP gt SSP
B
Phase of Common Raypath Cancels
x
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What is Seismic Interferometry?
Answer Correlation and summation of trace pairs
and stacking the result for different shot
positions

G(BB)
VSP gt SSP
B
Phase of Common Raypath Cancels
Do Not Need to Know Source Location! No Need to
know Source Initiation Time!
x
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Reciprocity Correlation Equation 2D Reflection
Data
k
Phase of Common Raypath Cancels
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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
Very Large Telescope Interferometer (VLTI Cerro
Paranal, Chile), which emulates a virtual
telescope about 100 meters across, and which
revealed a spherical molecular shell around the
aged star.
Stellar Interferometry
An astronomical interferometer is an array of
telescopes or mirror segments acting together to
probe structures with higher resolution.
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Standard VSP vs Interferometric VSP Imaging
Standard VSP Imaging
Interferometric VSP Imaging
Primary reflections
Multiple reflections
Small vs Huge Illumination
Instead of using just primary arrivals, you also
use the multiples for a wider vision
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Interferometry Applications
1. VSP -gt SSP
Small vs Huge Illumination
2. VSP -gt SWP
Redatum sources below overburden
Local VSP migration
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Interferometry Applications
3. SSP -gt SSP
Interpolation
4. OBS-gt OBS
Extrapolation
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Interferometry Applications
6. Passive Imaging
Monitoring 4D
7. Source Location
Monitoring EOR
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SELECTIVE HISTORY SEISMIC INTERFEROMETRY
!
Shell Virtual Sources