Critical Wavepath Refraction Migration
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Critical Wavepath Critical Wavepath Refraction Refraction Migration Migration Maike Buddensiek, Maike Buddensiek, University of Utah, University of Utah, Feb. 2003 Feb. 2003
description
Critical Wavepath Refraction Migration. Maike Buddensiek, University of Utah, Feb. 2003. Outline. Introduction - Why are we doing this? Basic concept of CRRM method Results of synthetic data Conclusions and further research. Introduction. - PowerPoint PPT Presentation
Transcript of Critical Wavepath Refraction Migration
Critical Wavepath Critical Wavepath Refraction MigrationRefraction Migration
Maike Buddensiek,Maike Buddensiek,
University of Utah, Feb. 2003University of Utah, Feb. 2003
OutlineOutline
• Introduction - Why are we doing this? Introduction - Why are we doing this?
• Basic concept of CRRM methodBasic concept of CRRM method
• Results of synthetic dataResults of synthetic data
• Conclusions and further researchConclusions and further research
IntroductionIntroduction
• Refraction data contain hidden Refraction data contain hidden information of reflection traveltimes.information of reflection traveltimes.
• After resorting the data, they are After resorting the data, they are kinematical equivalent to critical kinematical equivalent to critical reflections.reflections.
• Those critical refractions can be Those critical refractions can be migrated just like reflections.migrated just like reflections.
• Less artifacts Less artifacts
• Velocity of refracting layer not necessaryVelocity of refracting layer not necessary
• Any refractor geometry can be migratedAny refractor geometry can be migrated
BasicBasic ConceptConcept
A X M Y B
TAYTAY + TBX - TAB TAY + TBX TAY + TBX - TAB
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v2
Basic ConceptBasicBasic ConceptConcept
A X M Y B
TAYTAY + TBX - TAB TAY + TBX TAY + TBX - TAB
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Basic ConceptBasicBasic ConceptConcept
A X M Y B
TAYTAY + TBX - TAB TAY + TBX TAY + TBX - TAB
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Basic ConceptBasicBasic ConceptConcept
A X M Y B
TAYTAY + TBX - TAB TAY + TBX TAY + TBX - TAB = TXY
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TAY + TBX - TAB
BasicBasic ConceptConcept
A X M Y B
TXYdata : kinematics of reflection
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Critical Distance
TAY + TBX - TAB = TXY
Migration by RaytracingMigration by Raytracing
A X M Y B
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TXO + TOY = TXOYtheory
O
Incidence Angles for RaytracingIncidence Angles for Raytracing
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Migration by RaytracingMigration by Raytracing
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TXOYtheory TXY
data
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Migration by RaytracingMigration by Raytracing
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Critical Distance
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TXOYtheory = TXY
data
CRRM MethodCRRM Method• 1. Select A, B, X, Y and then trace rays1. Select A, B, X, Y and then trace rays
• 2. Determine T2. Determine TXOYXOYtheorytheory
• 3. Determine T3. Determine TXYXYdatadata
• 4. If T4. If TXYXYdatadata = T = TXOYXOY
theorytheory – Smear refraction energy at O. Smear refraction energy at O. – Otherwise no energy is smeared.Otherwise no energy is smeared.
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v2 O
A X M Y B
Dipping Layer Model 1Dipping Layer Model 1
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300
Dipping Layer Model 2Dipping Layer Model 2
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Low Frequency UndulationLow Frequency Undulation
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High Frequency UndulationHigh Frequency Undulation
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Fault ModelFault Model
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ResultsResults
• Very accurate mapping of the refractorsVery accurate mapping of the refractors
• No artifactsNo artifacts
• The refracting velocity is not knownThe refracting velocity is not known
• Problemaict zones just result in Problemaict zones just result in unmapped tracesunmapped traces
ConclusionConclusion
• The CRRM method has the potential to The CRRM method has the potential to migrate refraction data more precisely migrate refraction data more precisely than traditional methods.than traditional methods.
• CRRM does not produce artifacts like CRRM does not produce artifacts like traditional methods do.traditional methods do.
• Future Work: Make suggested changes Future Work: Make suggested changes and then apply to field data.and then apply to field data.
