Migration Deconvolution of 3-D Seismic Data Jianxing Hu (University of Utah) Paul Valasek (Phillips Petroleum Company)

Outline ProblemProblem SolutionSolution Numerical testsNumerical tests ConclusionsConclusions

Problems Migration noiseMigration noise Recording footprintRecording footprint 15km10km5km0km 0km 4km Poor ResolutionPoor Resolution Amplitude DistortionAmplitude Distortion Kirchhoff Migration Image

Modeling and Migration Seismic data Reflectivity Green’s Function Model Space Migrated Image Data Space Seismic Data Forward Modeling: Migration: Wavelet

Model Space Where: Denote as the migration Green’s Function Relation of Migrated Image and Reflectivity Distribution Relation of Migrated Image and Reflectivity Distribution Data Space

Reflectivity Modulated by Migration Green’s Function Model Space

Outline ProblemProblem SolutionSolution Numerical testsNumerical tests ConclusionsConclusions

Solution Get rid of the influence of migration green’s function from the migrated image Get rid of the influence of migration green’s function from the migrated image Method: Migration Deconvolution Migration Deconvolution

Migration Deconvolution Model Space Migration Green’s function lateral shift invariant Assumption: --- reference position of migration Green’s function

Outline ProblemProblem SolutionSolution Numerical testsNumerical tests ConclusionsConclusions

Numerical Tests 2-D SEG/EAGE overthrust model2-D SEG/EAGE overthrust model 3-D poststack Kirchhoff migration3-D poststack Kirchhoff migration of French model data set of French model data set 3-D poststack reverse time migration3-D poststack reverse time migration of a gulf of Mexico data set of a gulf of Mexico data set 3-D prestack Kirchhoff migration of3-D prestack Kirchhoff migration of a North Sea data set a North Sea data set

Velocity Model 0km 0km15km10km5km Depth (m) Velocity (m/sec)

Comparison of KM and MD 15 km 0 km 0 km 15 km 15 km Poststack Migration Image Poststack Migration Image Deconvolved Migration Image Deconvolved Migration Image 0 km 4 km 0 km 4 km

15 km 0 km 4 km 0 km 0 km 15 km 15 km Poststack Migration Image of Half Sampled Data Poststack Migration Image of Half Sampled Data Deconvolved Migration Image Deconvolved Migration Image 0 km 4 km Comparison of KM and MD

Prestack Migration Image Prestack Migration Image Deconvolved Migration Image Deconvolved Migration Image 0 km 20 km 20 km 0 km 4 km 20 km 0 km 0 km 0 km 4 km

Numerical Tests 2-D SEG/EAGE overthrust model2-D SEG/EAGE overthrust model 3-D poststack Kirchhoff migration3-D poststack Kirchhoff migration of French model data set of French model data set 3-D poststack reverse time migration3-D poststack reverse time migration of a gulf of Mexico data set of a gulf of Mexico data set 3-D prestack Kirchhoff migration of3-D prestack Kirchhoff migration of a North Sea data set a North Sea data set

French Model 10,000 ft/sec ,000 ft/sec 19,000 ft/sec 10,000 ft/sec 19,000 ft/sec Depth (km) 8 4 X (km) 2 Tested Area

Comparison of KM and MD Results Y (km) KM KM MD MD Depth (km) Depth (km) MD MD Depth (km) Depth (km) X (km) CrosslineSection InlineSection

Comparison of KM and MD Results Sharper Sharper X (km) Sharper X (km) Y (km) 534 KM KM MD MD 10,000 ft/sec 13,000 ft/sec 19,000 ft/sec Test Area Test Area X (km) Depth (km) m

Numerical Tests 2-D SEG/EAGE overthrust model2-D SEG/EAGE overthrust model 3-D poststack Kirchhoff migration3-D poststack Kirchhoff migration of French model data set of French model data set 3-D poststack reverse time migration3-D poststack reverse time migration of a gulf of Mexico data set of a gulf of Mexico data set 3-D prestack Kirchhoff migration of3-D prestack Kirchhoff migration of a North Sea data set a North Sea data set

Poststack RTM Image of a Gulf of Mexico Data Set X(km) X(km) Depth(km) Depth(km)

Velocity Model Depth (km) X (km) 6 1.6km/s 4.45km/s 3km/s

Comparison of RTM and MD Images 6 X(km) X(km) Depth (km) Depth (km) 1 6 X(km) X(km) Depth (km) Depth (km) RTMMD

Comparison of RTM and MD Images 3 Depth (km) Depth (km) Y(km) Y(km) Depth (km) Depth (km) Y(km) Y(km) RTM MD

Comparison of Depth Slices Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) RTM Image RTM Image MD Image MD Image Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km)

Comparison of Depth Slices RTM Image RTM Image MD Image MD Image Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km)

Numerical Tests 2-D SEG/EAGE overthrust model2-D SEG/EAGE overthrust model 3-D poststack Kirchhoff migration3-D poststack Kirchhoff migration of French model data set of French model data set 3-D poststack reverse time migration3-D poststack reverse time migration of a gulf of Mexico data set of a gulf of Mexico data set 3-D prestack Kirchhoff migration of3-D prestack Kirchhoff migration of a North Sea data set a North Sea data set

Comparison of PSKM and MD Images X (km) X (km) Depth (km) Depth (km) X (km) X (km) Depth (km) Depth (km) Prestack Kirchhoff Migration Image of Prestack Kirchhoff Migration Image of a North Sea Data Set a North Sea Data Set MD Image

KM Y(km) Y(km) Depth (km) Depth (km) Y (km) Y (km) Depth (km) Depth (km) MD Comparison of PSKM and MD Images

Comparison of Depth Slices 6 8 Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Kirchhoff Image Kirchhoff Image MD Image MD Image 6 8 Y (km) Y (km) X (km) X (km)

Comparison of Depth Slices 6 8 Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Kirchhoff Image Kirchhoff Image MD Image MD Image

Comparison of Decon and MD Images Depth (km) Depth (km) Depth (km) Depth (km) X (km) X (km) MD Image MD Image AGC + Harmonize + FXY decon image of the raw migration data

Comparison of Decon and MD Images 8 Y(km) Y(km) Depth (km) Depth (km) Y (km) Y (km) Depth (km) Depth (km) 8 MD AGC + Harmonize + FXY decon

Comparison of Depth Slices 6 8 Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Harmon + FXY Decon Image Harmon + FXY Decon Image MD Image MD Image 6 8 Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km)

Comparison of Depth Slices 6 8 Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Y (km) Y (km) X (km) X (km) Harmon + FXY Decon Image Harmon + FXY Decon Image MD Image MD Image

Results Comparison Model Deconvolved Migration Image ConventionalDeconvolution Migration MD Decon Kirchhoff Migration Image Kirchhoff Migration Image MD Image MD Image 0 X(km) X(km) Y(km) Y(km) 0 0 X(km) X(km) Y(km) Y(km) 1 1 MigrationImage

Outline MotivationMotivation SolutionSolution Numerical testsNumerical tests ConclusionsConclusions

Conclusions Works on 2D and 3D migrated data, improves resolution, mitigates migration artifactsWorks on 2D and 3D migrated data, improves resolution, mitigates migration artifacts Suitable for Kirchhoff and RTM migration imagesSuitable for Kirchhoff and RTM migration images Post-migration processingPost-migration processing

Acknowledgement Thank Phillips petroleum company and other UTAM sponsorsThank Phillips petroleum company and other UTAM sponsors Thank Phillips petroleum company, Veritas marine surveys, Agip (UK) ltd., BG EP ltd., Centrica plc., Conoco UK ltd., Fina exploration ltd., and Phillips (UK) ltd., for granting permission to present the application of MD to gulf of Mexico and North Sea data setThank Phillips petroleum company, Veritas marine surveys, Agip (UK) ltd., BG EP ltd., Centrica plc., Conoco UK ltd., Fina exploration ltd., and Phillips (UK) ltd., for granting permission to present the application of MD to gulf of Mexico and North Sea data set