Workshop 6
The value of multiples for seismic imaging and velocity model building
Sunday June 9th | Room 12
Convenors
- Gordon Poole (CGG)
- Clement Kostov (Consultant)
- Eric Verschuur (TU Delft)
- Nizar Chemingui (PGS)
- Fred Melo (SLB)
- James Mcleman (DUG)
- Simon Baldock (TGS)
Description
For many years multiples have been an enemy of the processing geophysicist, and much effort has been directed to their modelling and attenuation. More recently multiples have been recognized for the benefits they can bring to subsurface image illumination and full-waveform inversion (FWI). Some drawbacks of using the multiples have also been recognized, however, such as multiple contamination or cycle skipping.
In this workshop we will discuss the benefits and drawbacks multiples present in deriving the seismic image through multiple/full-wavefield migration and FWI. In which acquisition scenarios and subsurface conditions do the benefits outweigh the challenges of using multiples? How can we overcome the drawbacks of using multiples? In the case primaries richly illuminate the target, is there still value in using the multiples?
Sub-Topics that will be covered in the workshop:
- Model building and Imaging
- Imaging using multiples
- What can we do to minimise/avoid multiple cross-talk?
- Full-wavefield migration (FWM)
- Do internal multiples contribute to illumination in FWM?
- What challenges remain for FWM? Source wavelet? Sampling requirements? Balancing primary and multiple terms.
- Joint migration and velocity model building, what are the pros/cons compared to full-waveform inversion.
- Can separated primaries and multiples bring value to imaging?
- How can we improve imaging by combining the best of primary and multiple imaging.
- When high quality primaries are available, does FWM present more drawbacks the benefits?
- Imaging using multiples
- Full waveform inversion (FWI)
- In which environments do multiples help FWI?
- In which situations can multiples contaminate the FWI image? Relation to geological settings and scales at which relevant multiple scattering occurs.
- How can we overcome contamination in the FWI image?
- How well can FWI explain internal multiples?
- Can free-surface reflections help us derive properties of the subsurface, e.g. guided waves help estimate shallow Vp and Vs.
Participant Profile
Researchers, practitioners, students and decision makers interested in better understanding the value and challenges of multiples for seismic imaging and velocity model building.
Workshop Programme
| Time | Activity |
|---|---|
| 09:00 | Welcome - Gordon Poole (Viridien) |
| Session 1) Multiple imaging I. - Session: Chairs Gordon Poole (Viridien) & Nizar Chemingui (PGS) | |
| 09:10 | Exploring Multiples in Full Wavefield Imaging and Velocity Estimations Across Varied Geological Landscapes - Oystein Korsmo, PGS |
| 09:30 | Using multiples to image reflectors from above and below - Eric Verschuur, Delft |
| 09:50 | On the value of surface multiples in shallow-water streamer data - Fred Melo, SLB |
| 10:10 | Discussion |
| 10:30 | Coffee Break |
| . | Session 2) Multiple imaging II - Session Chairs: Eric Verschuur (Delft) & Clement Kostov |
| 10:50 | Cascaded least-squares multiple imaging for reduced multiple crosstalk - Milad Farshad, Viridien |
| 11:10 | Inversion of a shallow water-bottom ocean-bottom cable dataset using one-way modeling with multiple reflectivities Robert Soubaras, AkerBP |
| 11:30 | Incorporating Multiples for Accelerated Construction of Ground Models for Emerging Energy Applications - Nizar Chemingui, PGS |
| 11:50 | Discussion |
| 12:10 | Lunch Break |
| . | Session 3) Multiples in FWI I - Session Chairs: Fred Melo (SLB) & Gordon Poole (Viridien) |
| 13:40 | Is there a multiples free lunch? - Rodney Johnston, BP |
| 14:00 | On the use of multiples for imaging: a double-edged sword James Mcleman, DUG |
| 14:20 | Full Waveform Inversion for velocity model building and imaging with the full wavefield: are there any downsides? - Simon Baldock, TGS |
| 14:40 | Discussion |
| 15:00 | Coffee Break |
| . | Session 4) Multiples in FWI II - Session Chairs: Simon Baldock (TGS) & James Mcleman (DUG |
| 15:20 | Challenges and opportunities with multiples when marching towards images derived from high-frequency FWI - Olivia Lewis, SLB |
| 15:40 | Multiples in FWI ‐ turning problems into opportunities -Nikhil Shah, S-cube |
| 16:00 | Advancing the use of marine DAS-VSP data for reservoir characterization and monitoring by utilizing the full seismic wavefield -Fa qi Lu, TGS |
| 16:20 | Title TBC - Per Eivend Dhelie, Aker BP |
| 16:40 | Discussion |
| 17:00 | Workshop Ends |
