Multi-Component Seismic, Principles and Applications

by Robert J. Garotta

Duration: Two days

Summary:
Participants will learn the theory and practice of shear wave data from acquisition, through processing, to interpretation.

Course Outline:
The first part of the course is devoted to overcoming the difficulties associated with shear wave acquisition. Converted mode operation is covered in detail using real-life examples. The particularities of sea bottom receivers are also examined.

The second part of the course reviews the processing and the main challenges of the shear converted modes: static corrections, gathering, velocity analysis and compensation for shear wave splitting in axial anisotropy. The course gives a detailed description of processing sequences. 2D and 3D results, yielding natural axis orientation of layers, are compared in shear and PS converted modes.

The third part of the course is devoted to case histories where new attributes, such as Vp/Vs ratio, crack density, or fracture orientation, are illustrated in a reservoir characterization context. These case histories can guide the geophysicist to decide if a particular geological situation can be best handled using shear waves.

Learner Outcomes

  1. Recognize how successive scientific or technological advances lead to the present applications of multi-component seismic
  2. Explain how early users would justify multi-component seismic and indicate the main trends
  3. Identify:
    1. how many elastic parameters characterize an isotropic or anisotropic environment
    2. which wave modes propagate in a given environment
    3. how many elastic parameters can be delivered by multi-component seismic
    4. how different wave modes induce different reflectivity responses
    5. how different wave modes are affected by different surface waves
  4. Explain wave modes conditioned by a given environment:  polarization, velocity, attenuation and absorption
  5. List the source and receiver specifics for acquiring multi-component data in land or marine
  6. Adjust land or marine acquisition parameters
  7. Design land or marine multi-component surveys
  8. Process pure shear mode data in a VTI environment
  9. Process PS converted mode data in a VTI environment
  10. Derive high resolution VP/VS ratio through PP-PS joint inversion
  11. Detect azimuthal anisotropy
  12. Process pure shear mode or PS converted mode data in case of azimuthal anisotropy
  13. Derive and display azimuthal anisotropy attributes

Method of Assessment: Online multiple choice test

Instructor Biography:
Robert J. Garotta