"Geophysics plays a central role in this energy transition because it provides the tools and insights needed to understand, manage, and optimize subsurface resources. These resources are critical for both traditional and renewable energy systems."
Geophysics is essential for geothermal energy, carbon storage, hydrogen storage, and critical minerals. Joël Le Calvez and Erkan Ay explain how methods like multi-physics workflows and distributed acoustic sensing are improving reliability, scalability, and safety. They also highlight the skills and mindset geophysicists need to succeed in a rapidly changing energy landscape.
Read the October issue of The Leading Edge that features a special section about geophysics for new energies at https://library.seg.org/toc/leedff/44/10.
KEY TAKEAWAYS
> Geophysics provides the foundation for safe, efficient, and scalable use of subsurface resources in the energy transition.
> Multi-physics workflows and DAS technologies reduce uncertainty and improve monitoring of geothermal and storage projects.
> Future geophysicists must combine technical expertise with adaptability, collaboration, and field experience.
GUEST BIOS
Joël Le Calvez is Principal Geologist at SLB, where he develops software for processing, visualization, and interpretation of microseismic monitoring data. His work supports applications ranging from hydraulic fracture treatment to CO₂ sequestration and geothermal injection, using downhole, shallow wellbore, and surface arrays. Before joining SLB, Joël contributed to research at the Bureau of Economic Geology’s Applied Geodynamics Laboratory and at Etudes et Recherches Géotechniques. He holds a Ph.D. in salt tectonics, an M.Sc. in geosciences, and a B.Sc. in physics.
Erkan Ay is an accomplished geophysicist with more than 18 years of international experience across oil and gas, carbon capture and storage, and academic research. He is recognized for advancing techniques in microseismic monitoring, DAS, 4D VSP, and seismic-while-drilling. Erkan’s work integrates seismology and petrophysics to better characterize complex subsurface structures. Currently, Erkan serves as Chair of the SEG Research Committee and Vice Chair of the SEG IMAGE 2026 Technical Committee, guiding collaborative efforts to advance geophysics for sustainable energy solutions.
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"Geophysics plays a central role in this energy transition because it provides the tools and insights needed to understand, manage, and optimize subsurface resources. These resources are critical for both traditional and renewable energy systems."
Geophysics is essential for geothermal energy, carbon storage, hydrogen storage, and critical minerals. Joël Le Calvez and Erkan Ay explain how methods like multi-physics workflows and distributed acoustic sensing are improving reliability, scalability, and safety. They also highlight the skills and mindset geophysicists need to succeed in a rapidly changing energy landscape.
Read the October issue of The Leading Edge that features a special section about geophysics for new energies at https://library.seg.org/toc/leedff/44/10.
KEY TAKEAWAYS
> Geophysics provides the foundation for safe, efficient, and scalable use of subsurface resources in the energy transition.
> Multi-physics workflows and DAS technologies reduce uncertainty and improve monitoring of geothermal and storage projects.
> Future geophysicists must combine technical expertise with adaptability, collaboration, and field experience.
GUEST BIOS
Joël Le Calvez is Principal Geologist at SLB, where he develops software for processing, visualization, and interpretation of microseismic monitoring data. His work supports applications ranging from hydraulic fracture treatment to CO₂ sequestration and geothermal injection, using downhole, shallow wellbore, and surface arrays. Before joining SLB, Joël contributed to research at the Bureau of Economic Geology’s Applied Geodynamics Laboratory and at Etudes et Recherches Géotechniques. He holds a Ph.D. in salt tectonics, an M.Sc. in geosciences, and a B.Sc. in physics.
Erkan Ay is an accomplished geophysicist with more than 18 years of international experience across oil and gas, carbon capture and storage, and academic research. He is recognized for advancing techniques in microseismic monitoring, DAS, 4D VSP, and seismic-while-drilling. Erkan’s work integrates seismology and petrophysics to better characterize complex subsurface structures. Currently, Erkan serves as Chair of the SEG Research Committee and Vice Chair of the SEG IMAGE 2026 Technical Committee, guiding collaborative efforts to advance geophysics for sustainable energy solutions.
From Differences to Inversion: A New Era for 4D Seismic
Seismic Soundoff
26 minutes 19 seconds
3 months ago
From Differences to Inversion: A New Era for 4D Seismic
“Repeatability is the biggest hurdle in time-lapse monitoring, but it’s also where the opportunity lies. 4D FWI can help address those repeatability challenges.”
On this episode, Andrew Geary sits down with Madhav Vyas and Kris Innanen, guest editors for July’s The Leading Edge special section on 4D full-waveform inversion. They explain how 4D FWI goes beyond traditional differencing by fully inverting wavefields, making time-lapse seismic more robust against survey inconsistencies and complex overburden. Listeners will learn why now is the perfect time to adopt 4D FWI, the main technical hurdles around repeatability and uncertainty, and the first steps to take for reservoir monitoring and survey design.
KEY TAKEAWAYS
> 4D FWI inverts the full wavefield - reflections, refractions, diving waves, multiples - to detect reservoir changes, making it more robust than conventional 4D processing.
> Repeatability of surveys and assessing uncertainty are the biggest challenges, but workflows like hypothesis testing, batch FWI, and null-space shuttling help mitigate inversion noise.
> High-quality data and accurate physics (elasticity, attenuation, anisotropy) are essential; advances in GPU-driven computation enable faster iterations and richer uncertainty analysis.
CALL TO ACTION
Read July's The Leading Edge special section on 4D FWI at https://library.seg.org/toc/leedff/44/7, then explore an open-source FWI toolbox.
LINKS
* Visit https://seg.org/podcasts/episode-265-from-differences-to-inversion-a-new-era-for-4d-seismic for the complete show notes.
Seismic Soundoff
"Geophysics plays a central role in this energy transition because it provides the tools and insights needed to understand, manage, and optimize subsurface resources. These resources are critical for both traditional and renewable energy systems."
Geophysics is essential for geothermal energy, carbon storage, hydrogen storage, and critical minerals. Joël Le Calvez and Erkan Ay explain how methods like multi-physics workflows and distributed acoustic sensing are improving reliability, scalability, and safety. They also highlight the skills and mindset geophysicists need to succeed in a rapidly changing energy landscape.
Read the October issue of The Leading Edge that features a special section about geophysics for new energies at https://library.seg.org/toc/leedff/44/10.
KEY TAKEAWAYS
> Geophysics provides the foundation for safe, efficient, and scalable use of subsurface resources in the energy transition.
> Multi-physics workflows and DAS technologies reduce uncertainty and improve monitoring of geothermal and storage projects.
> Future geophysicists must combine technical expertise with adaptability, collaboration, and field experience.
GUEST BIOS
Joël Le Calvez is Principal Geologist at SLB, where he develops software for processing, visualization, and interpretation of microseismic monitoring data. His work supports applications ranging from hydraulic fracture treatment to CO₂ sequestration and geothermal injection, using downhole, shallow wellbore, and surface arrays. Before joining SLB, Joël contributed to research at the Bureau of Economic Geology’s Applied Geodynamics Laboratory and at Etudes et Recherches Géotechniques. He holds a Ph.D. in salt tectonics, an M.Sc. in geosciences, and a B.Sc. in physics.
Erkan Ay is an accomplished geophysicist with more than 18 years of international experience across oil and gas, carbon capture and storage, and academic research. He is recognized for advancing techniques in microseismic monitoring, DAS, 4D VSP, and seismic-while-drilling. Erkan’s work integrates seismology and petrophysics to better characterize complex subsurface structures. Currently, Erkan serves as Chair of the SEG Research Committee and Vice Chair of the SEG IMAGE 2026 Technical Committee, guiding collaborative efforts to advance geophysics for sustainable energy solutions.
