My simple request for IMAGE22 is for the program to be far more navigable, and for the presentations to be available on demand within half a day of their scheduled time. There is a huge global community who will benefit from being able to better follow such programs in a virtual manner.
After a week of hiccups, the IMAGE21 presentations largely became available at the end of last week, and I will comment on two elements of the aptly-named IMAGE program:
- Advances in seismic imaging
- The image of the geoscience community to the next generation of geoscientists
Better Seismic Images and Faster
As I noted last week, the two highest-profile marine seismic technologies were (again) FWI (full waveform inversion), and the related acquisition platforms of OBN (ocean bottom node) and towed streamer seismic. Now that acoustic FWI has become tractable for vast survey scales, attention has understandably progressed to the ‘next degree’ of sophistication. That progress means exploiting the advances in acquisition platforms for FWI to work better, and it means expanding the deliverables produced by FWI.
On one hand, the use of OBN as the standalone acquisition platform for imaging complex areas or areas affected by obstructions and shallow water is growing in areas with proven assets. And OBN and has grown much faster as a way to augment towed streamer surveys with ultra-long offsets in a manner beneficial to the stability of refraction FWI.
In all OBN cases, there are many FWI solutions that can demonstrably yield significantly more accurate velocity models, and proliferation of IMAGE21 talks showed before and after examples of seismic images with quite profound improvements—although the ‘improved’ images in salt provinces are often dominated by low-resolution coherent events. Some of these improved images also incorporate the computation of shear-wave velocity models into converted-wave imaging. Technology breakthroughs that enabled these results include revised forms of the acoustic wave equation to improve the modeled contribution of reflections from deeper reflectors and more robust solutions to mitigate cycle-skipping effects.
On the other hand, there are several emerging efforts to either use the FWI kernel as a proxy for higher-resolution imaging or expand the FWI kernel to effectively provide a joint model building and LSM (least-squares migration) solution. One of the drivers for such pursuits is the ambition to compress traditionally cascaded preconditioning and imaging workflows into an elegant solution that delivers interpretation products in a short timeframe.
Traditional FWI incorporates much of the full seismic wavefield, including multiples, into the forward modeling component of the adjoint solution. Correspondingly, the output model—traditionally velocity—has superior illumination to that imaged with the migration of reflections only. New results at IMAGE21 show one can either translate the velocity model to a higher spatial resolution pseudo image using spatial derivatives or directly solve for a fully migrated high-resolution reflectivity image in the manner of Yang et al.
A Brave New World?
If you dig through the quite vast IMAGE21 program, the themes of carbon capture and storage (CCS) and the renewed interest in mining for strategic metals were evident. But several conference participants, most notably from the next generation of geoscientists yet to establish their careers, anxiously observed that the SEG and AAPG talks overwhelmingly represent their roots in petroleum exploration. What does the future hold? Like any corporation seeking to reposition itself and find financial security, our industry needs some vision of what the future might hold, so that the employees can align themselves with that strategic direction. Can the SEG and AAPG provide an ‘image of the future’ for our next generation of geoscientists—before they turn away?
Thanks to covid pressures, the annual EAGE conference was delayed from June to later this month. Given that the EAGE historically has a broader geoscience and engineering landscape than the SEG events, it will be interesting to contrast the two largest annual geoscience events in rapid succession. And it will be worth again asking whether sufficient strategic direction is being offered to our next generation.
The Big Question
Finally, for those who registered for IMAGE21 access, I point to an interesting talk by William DeMis in the Monday session ‘Theme 10: Surface and Sub-Surface Risk Assessment’, which was titled ‘History Suggests Nominal Oil Prices Could Rise to $200 a Barrel in Near Future’. The AAPG program contained an interesting mix of case study hardcore geological analyses and an eclectic collection of far broader themes. I hope these can be interwoven more seamlessly into future IMAGE events with the technical SEG content.
Today we see two-thirds of China affected by rolling power shortages, and large parts of Europe affected by surging gas prices. The reasons are several, but are a reminder that the world will depend upon fossil fuels for many years ahead. If we neglect exploration, it will not take much to trigger global crises, and so we need to sensibly combine the transition to lower carbon energy sources with sustainable cost of living.
Anyway, global events over the past 80 years were used by DeMis to illustrate the factors that influence our global economy today. Most notably, once inflation kicks in, there are strong arguments that the price of oil could easily rise to US$200 per barrel. What would happen to the energy transition discussion if the price of oil was sustained at such high levels? It is pretty clear that the seismic method still has a vast future role to play in both conventional and low carbon energy generation. Before it’s too late, our image to the world around us needs to reinforce the importance of a sensible and responsible transition to an affordable mix of energy resources.