Description

The main objectives of the project are
• Study the sensitivity of different types of waves to some elastic changes, both in terms of both kinematics (time delays) and dynamics (amplitude modifications);
• Propose a strategy to map the changes (recorded by the waves at the surface in the time domain) to some subsurface locations (i.e. construct partial images to locate the changes in depth);
• Assess uncertainties (Bayesian context) on the modifications of the subsurface images by considering different sources of uncertainties, while respecting a priori information;
• Design an optimal acquisition geometry to capture the changes and to discriminate between different scenarios; take into account operational constraints;
• Validate on real data sets;
• Play a central role in the collaboration between Mines Paris, SpotLight Earth and clients who provide the real data sets.

The PhD student will benefit from existing numerical modelling tools to investigate the potential of different types of waves for monitoring the subsurface. He/she will develop a specific imaging tool, considering sparse data and a specific data type.

Skills required

The PhD student should have a strong background in mathematics, physics and signal processing, as well as good scientific programming capabilities. He/she should be interested in geophysics and more precisely in seismic modelling and imaging. He/she should be motivated by developing academic projects with an industrial impact. Contacts and Places of Work Pr. Hervé Chauris Email: herve.chauris@minesparis.psl.eu Tel: +33 1 64 69 49 13 Mines Paris - PSL Research University 35 rue Saint-Honoré 77305 Fontainebleau Cedex, France Dr. Nour Mikhael Email: nour@spotlight-earth.com Tel: +33 1 83 64 75 84 SpotLight Earth 37 rue du Saule Trapu, 91300 Massy, France

Bibliography

References
• Al Khatib, H., Boubaker, Y., and Morgan, E. (2021). Breaking the seismic 4D
‘image’ paradigm of seismic monitoring. First Break, 39(9):85–91. Number: 9
• Al Khatib, H. and Morgan, E. (2025). Trigger Seismic CCS surveillance: Not to
image, but to know when to image. First Break, 43(10):27–91.
• Chauris, H. (2019). Full Waveform Inversion, in Seismic Imaging, a practical
approach , J-L. Mari and M. Mendes (Eds.), EDP Sciences, chapter 5, 23 p.,
ISBN (ebook): 978-2-7598-2351-2, doi:10.1051/978-2-7598-2351-2.c007
• Chauris, H. and E., Cocher (2017), From migration to inversion velocity
analysis, Geophysics 82(3): S207–S223, doi:10.1190/GEO2016-0359.1
• Cotton, J., É. Forgues and H. Chauris (2018), Time-lapse velocity analysis –
application to onshore continuous reservoir monitoring, Geophysics 83(3):
B105–B117, doi:10.1190/geo2017-0014.1
• El Khoury, C., A. Kazantsev and H. Chauris (2024), The influence of an
anticline structure on ambient noise spectral anomalies at an underground
gas storage, 237: 1061–1078 Geophysical Journal International,
doi:10.1093/gji/ggae089
• Fachtony, F.A., R. Brossier, B. Boddupalli, B. Dupuy, L. Metivier and A.
Romdhane (2025). CO2 monitoring at sleipner field using reflection oriented
Full Waveform Inversion - part 1: baseline reconstruction. Geophysical
Journal International, 241(2):1226-1242, https://doi.org/10.1093/gji/ggaf097
• Fachtony, F.A,, R. Brossier, B. Boddupalli, B. Dupuy, L. Metivier and A.
Romdhane (2025). CO2 monitoring at Sleipner field using reflection oriented
Full Waveform Inversion: part 2 - 4d investigation. Geophysical Journal
International, 242(1):ggaf185, http://dx.doi.org/10.1093/gji/ggaf185

Keywords

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