N282 Introduction to Full Azimuth Imaging for Conventional Plays and Resource Plays

Course Facts

Course Code:
N282
Duration:
4 days
Type:
Classroom
CEU:
3.2 Continuing Education Units
PDH:
32 Professional Development Hours
Certificate:
Certificate Issued Upon Completion

Summary

This course is for seismic interpreters and data processors seeking to gain a practical understanding of the current commercial methods of seismic imaging with an emphasis on full azimuth imaging. Participants will receive the knowledge required to make informed decisions regarding which processing and imaging algorithms to use, how to build and update velocity models, and learn to effectively design, guide, and quality control full-azimuth, full-offset imaging projects in a variety of geological settings. Participants will learn methodologies to compute, quality control and incorporate azimuthal seismic attributes with isotropic seismic attributes and reservoir information.

Duration and Training Method

This is a four-day classroom course using a combination of lectures, demonstrations, case histories, and hands-on practical work exercises.

Participants will learn to:

  1. Distinguish the fundamental differences between time and depth migration.
  2. Differentiate between commonly used imaging algorithms including ray and wave-equation techniques.
  3. Understand current marine and land acquisition techniques used for wide/full azimuth imaging.
  4. Understand current processing and imaging strategies to obtain desired products for conventional and resource plays.
  5. Monitor the data conditioning stages of the initial processing sequence.
  6. Provide the appropriate interpretation inputs to the velocity model building process, and verify that the form of the velocity model is appropriate for the geology of the project.
  7. Understand the benefits, as well as the technical challenges, presented by full-azimuth, full-offset 3D data sets. Special emphasis will be placed on the conditioning of data to obtain, and the computation, uncertainty and use of, azimuthal interval velocity and azimuthal amplitude information.
  8. Incorporate seismic/well tie information that can be used as a constraint for velocity modeling and the determination of anisotropy parameters.
  9. Prepare and QC post-imaging data for isotropic and azimuthal simultaneous inversions.

The course content is divided into 8 chapters. On the last day, time will be provided for an open forum discussion of several client projects and case histories. Participants are encouraged to bring data examples to the class for general discussion.

Chapter 1: Introduction and the Reflection Seismic Experiment

Chapter 2: Full/wide Azimuth Seismic Background

  • Marine, land and ocean bottom acquisition
  • Simultaneous source shooting

Chapter 3. Basics of Seismic Imaging

  • What is migration?
  • Ray theoretical time-to-depth conversion
  • Zero-offset time migration
  • Zero-offset depth migration
  • Imaging principles for zero-offset migration
  • Image sensitivity to migration velocity
  • Migration artifacts

Chapter 4. Data Conditioning with Emphasis on Wide Azimuth Processes

  • Improving resolution
  • Seismic datums
  • Initial velocity analysis
  • Refraction/reflection statics
  • Multiple identification and suppression

Chapter 5. 3D Migration/Imaging

  • Depth migration vs. time migration - background
  • Depth migration vs. time migration - examples
  • Pre-stack migration imaging principles
  • Data acquisition considerations
  • Data organization and binning for azimuthal imaging
  • Use of 5-D interpolation
  • Choosing an algorithm
  • Migration parameterization, testing and quality control

Chapter 6. Migration Velocity Analysis and Velocity Model Updating

  • Building an initial migration velocity field
  • Basic concepts of MVA
  • Tomographic velocity model parameterization and updating
  • Estimating and incorporating layer anisotropy
  • Estimating and incorporating azimuthal anisotropy
  • Full-waveform inversion
  • Salt flooding
  • Velocity and image uncertainty

Chapter 7: Post-imaging Analysis

  • Interpretation in time vs. depth
  • Post-imaging time-depth conversion
  • Incorporating other seismic attributes
  • Co-rendering azimuthal and isotropic attributes
  • Off set and refl ection-angle common-image-point gathers
  • Preparation and QC of pre-stack migrated data for simultaneous inversions

Chapter 8: Case Histories

  • Land
  • Marine
  • Ocean-bottom seismic
  • Simultaneous sources

Who should attend

This course should be of interest to all seismic interpreters and data processors planning to incorporate depth imaging into their exploration and/or exploitation projects. Resource plays and sub-salt reservoirs present special imaging challenges that are addressed in this course.

Prerequisites and linking courses

Participants should be familiar with the fundamentals of the seismic method and have some interpretation experience before attending this class. Participants can fulfill these prerequisites by first attending Nautilus Training Alliance course N085 "Introduction to Seismic Interpretation" or N080 "Geophysics for Subsurface Professionals", or equivalent training.

Since velocity modeling is at the heart of seismic depth imaging, participants should also consider taking courses such as N002 "Velocities for Depth Conversion", or N172 "Depth Conversion: Methods and Pitfalls" beforehand.

Participants in N282 wanting to learn more about the theory underlying the various algorithms should consider taking N217 "Seismic Imaging and Velocity Model-Building Techniques".

Click on a name to learn more about the instructor

Walt Lynn

Gave me an understanding of current status of PSDM and wave imaging.