reverse time migration of multiples for obs data dongliang zhang kaust
TRANSCRIPT
Outline
Conclusions
MotivationWider illumination, no footprint artifacts
Numerical ExampleTest on Marmousi model and field data
TheoryReverse time migration of multiples
Outline
Conclusions
MotivationWider illumination, no footprint artifacts
Numerical ExampleTest on Marmousi model and field data
TheoryReverse time migration of multiples
Motivation
Migration Image of Primary
No footprint artifacts Wider illumination
Migration Image of Multiples
reciprocity
Outline
Conclusions
MotivationWider illumination, no footprint artifacts
Numerical ExampleTest on Marmousi model and field data
TheoryReverse time migration of multiples
Multiples RTM of Streamer Data
ReceiverSource
1st- order multiple
2nd- order multiple
……
primary image artifact artifact
1st- order multiple
artifact image artifact
2nd- order multiple
artifact artifact image
……
time MultiplePrimary
Data
Multiples
Multiples RTM of Streamer Data
ReceiverSource
primary 1st- order multiple
2nd- order multiple
……
primary artifact image artifact artifact
1st- order multiple
artifact artifact image artifact
2nd- order multiple
artifact artifact artifact image
……
time MultiplePrimary
Data
Data
Up-going wave
Down-going wave
Combine up-going & down-going waves
Multiples RTM of OBS Data
• Don’t need to separate up-going and down-going wave
• Same procedure as up-going and down-going wave
Illumination of Primary for One Shot
Illumination of Multiples for One Shot
Illumination: Primary vs Multiples
Outline
Conclusions
MotivationWider illumination, no footprint artifacts
Numerical ExampleTest on Marmousi model and field data
TheoryReverse time migration of multiples
1.5
k
m/s
5.5
True Velocity Model
0 X (km) 9
3.5
Z
(km
)
0
Marmousi Model
Full Data
6
T (
s)
0
0 X (km) 9
Direct Wave & Primary
0 X (km) 9
Multiples
0 X (km) 9
Image of Primary Vs Multiples3.
5
Z (
km)
0
Primary Image with R.I. 50 m Multiples Image with R.I. 50 m
0 X (km) 9
3.5
Z
(km
)
0
0 X (km) 9
Primary Image with R.I. 100 m Multiples Image with R.I. 100 m
Image of Primary Vs Multiples3.
5
Z (
km)
0
Primary Image with R.I. 200 m Multiples Image with R.I. 200 m
0 X (km) 9
3.5
Z
(km
)
0
0 X (km) 9
Primary Image with R.I. 400 m Multiples Image with R.I. 400 m
Field Data
Receivers: 9 Interval: 400m
Sources: 124Interval: 75m
Water Depth: 40m
12
T
(s)
0
0 X (km) 9
Common Receiver Gather
Outline
Conclusions
MotivationWider illumination, no footprint artifacts
Numerical ExampleTest on Marmousi model and field data
TheoryReverse time migration of multiples