the earth’s near surface as a vibroseis signal generator

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The Earth’s Near Surface as a The Earth’s Near Surface as a Vibroseis Signal Generator Vibroseis Signal Generator Zhiyong Jiang Zhiyong Jiang University of Utah University of Utah

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The Earth’s Near Surface as a Vibroseis Signal Generator. Zhiyong Jiang. University of Utah. Outline. Introduction Methodology Synthetic Data Test Conclusions. Motivation: in Indonesia gas hydrates blur the reflections. g. s. s’. x. Outline. Introduction Methodology - PowerPoint PPT Presentation

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Page 1: The Earth’s Near Surface as a Vibroseis Signal Generator

The Earth’s Near Surface as The Earth’s Near Surface as a Vibroseis Signal Generatora Vibroseis Signal Generator

Zhiyong JiangZhiyong Jiang

University of UtahUniversity of Utah

Page 2: The Earth’s Near Surface as a Vibroseis Signal Generator

OutlineOutline

• IntroductionIntroduction• MethodologyMethodology• Synthetic Data TestSynthetic Data Test• ConclusionsConclusions

Page 3: The Earth’s Near Surface as a Vibroseis Signal Generator

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Motivation: in Indonesia gas Motivation: in Indonesia gas hydrates blur the reflectionshydrates blur the reflections

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Page 4: The Earth’s Near Surface as a Vibroseis Signal Generator

OutlineOutline

• IntroductionIntroduction• MethodologyMethodology• Synthetic Data TestSynthetic Data Test• ConclusionsConclusions

Page 5: The Earth’s Near Surface as a Vibroseis Signal Generator

Review: 1st-order Multiple Imaging with Review: 1st-order Multiple Imaging with Crosscorrelation MigrationCrosscorrelation Migration

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Page 6: The Earth’s Near Surface as a Vibroseis Signal Generator

Review: 1st-order Multiple Imaging with Review: 1st-order Multiple Imaging with Crosscorrelation MigrationCrosscorrelation Migration

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Page 7: The Earth’s Near Surface as a Vibroseis Signal Generator

Review: Near Surface Scattering Decon.Review: Near Surface Scattering Decon.

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Page 8: The Earth’s Near Surface as a Vibroseis Signal Generator

Review: Near Surface Scattering Decon.Review: Near Surface Scattering Decon.

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Page 9: The Earth’s Near Surface as a Vibroseis Signal Generator

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Page 10: The Earth’s Near Surface as a Vibroseis Signal Generator

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Page 11: The Earth’s Near Surface as a Vibroseis Signal Generator

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Why name it “EAV” (Earth as a Why name it “EAV” (Earth as a vibroseis signal generator)vibroseis signal generator)

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Pilot signalPilot signalVibroseis traceVibroseis trace

Page 12: The Earth’s Near Surface as a Vibroseis Signal Generator

OutlineOutline

• IntroductionIntroduction• MethodologyMethodology• Synthetic Data TestSynthetic Data Test• ConclusionsConclusions

Page 13: The Earth’s Near Surface as a Vibroseis Signal Generator

Velocity ModelVelocity Model

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Shots: 676; Receivers: 50 (1100m -1600m)Shots: 676; Receivers: 50 (1100m -1600m)

Page 14: The Earth’s Near Surface as a Vibroseis Signal Generator

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Page 15: The Earth’s Near Surface as a Vibroseis Signal Generator

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Page 16: The Earth’s Near Surface as a Vibroseis Signal Generator

EAV to Upgoing ComponentEAV to Upgoing Component

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Page 17: The Earth’s Near Surface as a Vibroseis Signal Generator

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Page 18: The Earth’s Near Surface as a Vibroseis Signal Generator

Primary Migration ImagePrimary Migration Image

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Page 19: The Earth’s Near Surface as a Vibroseis Signal Generator

11stst-order Multiple with -order Multiple with Crosscorrelation MigrationCrosscorrelation Migration

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Page 20: The Earth’s Near Surface as a Vibroseis Signal Generator

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Page 21: The Earth’s Near Surface as a Vibroseis Signal Generator

OutlineOutline

• IntroductionIntroduction• MethodologyMethodology• Synthetic Data TestSynthetic Data Test• ConclusionsConclusions

Page 22: The Earth’s Near Surface as a Vibroseis Signal Generator

ConclusionConclusion

• Free surface points can be regarded as Free surface points can be regarded as vibroseis signal generator, and direct waves, vibroseis signal generator, and direct waves, primary reflections, multiple reflections can primary reflections, multiple reflections can be regarded as the pilot signal, the response be regarded as the pilot signal, the response can be thought of as vibroseis tracecan be thought of as vibroseis trace

• With EAV, a ringy trace can be compressed With EAV, a ringy trace can be compressed into an impulsive primary reflectioninto an impulsive primary reflection

Page 23: The Earth’s Near Surface as a Vibroseis Signal Generator

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Pilot Pilot signalsignal

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Future work: use EAV to deblur the scattering due Future work: use EAV to deblur the scattering due to gas hydrates near the sea floor to gas hydrates near the sea floor

Page 24: The Earth’s Near Surface as a Vibroseis Signal Generator

We thank UTAM sponsors for their We thank UTAM sponsors for their financial supportfinancial support

AcknowledgmentsAcknowledgments