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GEOM. VEL ANAL. Basic Seismic Processing. INPUT. FILTER. CMP Gather. NMO. MUTE. STATICS. STACK. MIGRATE. DISPLAY. More Seismic Processing. NMO. FK FILTER. GAIN RCVR. GEOM. INPUT. DECON. MUTE. EDIT. COHERENCY ENHANCE. BP FILTER. CMP Gather. DEMUX. STATICS. MIGRATE.
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GEOM VEL ANAL Basic Seismic Processing INPUT FILTER CMP Gather NMO MUTE STATICS STACK MIGRATE DISPLAY
More Seismic Processing NMO FK FILTER GAIN RCVR GEOM INPUT DECON MUTE EDIT COHERENCY ENHANCE BP FILTER CMP Gather DEMUX STATICS MIGRATE FK FILTER DMO/ MIGRATE TIME TO DEPTH VIB CORR DECON VEL ANAL STACK COHERENCY ENHANCE DISPLAY SAVE
Migration actual Seismic section (unmigrated) Migration(move it back) sin() = tan (a), where = true dip, a = apparent dip
Migration Effects Models (perfectly migrated) Synthetic Seismic Sections (Unmigrated)
Diffraction Point Reflector (Diffractor) Reflection Response (Diffraction)
Diffraction Model of Generic Reflection Multiple diffractors Dx = finite Multiple diffractors Dx 0
Migration with Velocity Distortion Layer 1 Layer 2 Layer 3 ALL
Depth Migration & Stack Smearing Zero-0ffset (Single fold) 10 Fold Stack
Migration Ex: Syncline Before After Migration ?
Migration Ex: Fault Before Migration After Migration
Migration Example Before Migration After Migration
Migration: Methodology unmigrated migrated Wavefront Summation (Kirchoff Stack) Diffraction Summation (Diffraction Stack)
Migration Methodology Exploding Reflector (Back Propagation, Wave Equation Finite Difference, FK)
Migration Artifacts: Aperture 35 traces 70 traces 150 traces 256 traces
Migration Artifacts: Velocity True V V 5% low V 10% low V 20% low
Migration and Noise Unmigrated Migrated Random Noise Random Noise + Migration Migration “smiles” esp at edges of data
Migration: Voila Note: Steep dip migration