Christophe Zaroli

Home page of Dr. Christophe Zaroli

Lecturer at the University of Strasbourg — Maître de conférences (hors classe, HDR)

Teaching @ EOST:

  • Mathematics & computer science (applied to geophysics).

Research @ ITES:

  • Seismology / Seismic tomography 
  • Development of new methods (SOLA–Backus–Gilbert tomography).
  • Seismic imaging of the Earth's interior at various scales

My research —recent years:

  • I have introduced and adapted the SOLA method to solve tomographic problems*  (Zaroli, 20162019; Zaroli et al. 2017), and named it: SOLA tomography :-)
  • The SOLA method (Subtractive Optimally Localized Averages; Pijpers & Thompson, 1992) is a variant of Backus & Gilbert's inverse theory (Backus & Gilbert, 1967, '68, '70).
  • *Problems must be linear(-izable), but can be of large scale —and the model space can be treated using either a discrete (Zaroli 2016) or a continuous (Zaroli 2019) formalism.

Some advantages of SOLA tomography:

  • Models are accompanied with information on their resolution and uncertainty.
  • Direct control on resolution/uncertainty.
  • No a priori constraints on model parameters (but on model resolution).
  • Models can be free of averaging-bias effects, and fit the data.
  • Data-kernels can be fully exploited (if no model space discretization).
  • Natural framework for tomographic-geodynamic comparisons.
  • Development of dVp and dVs models at comparable resolution (to infer R=dVs/dVp).
  • Development of dVsh and dVsv models at comparable resolution (to infer anisotropy).
  • And more...!

Watch my talk on SOLA tomography (Collège de France, Paris, 2021):

Peer-reviewed publications related to SOLA tomography (see 'Publications'):

  • Zaroli, 2016, GJI (download)
  • Zaroli, Koelemeijer, Lambotte, 2017, GRL (download)
  • Voronin & Zaroli, 2018, InTechOpen Book (download)
  • Zaroli, 2019, GJI (download)
  • Freissler (MSc student), Zaroli, Lambotte, Schuberth, 2020, GJI (download)
  • Latallerie (PhD student), Zaroli, Lambotte, Maggi, 2022, GJI (download)
  • Amiri (PhD student), Maggi, Tatar, Zigone & Zaroli, 2023, Seismica (download)
  • Restelli (PhD student), Zaroli, Koelemeijer, 2024, PEPI (download)
  • Freissler (PhD student), Schuberth, Zaroli, 2024, GJI (download preprint)
  • And more coming soon... :-)

Ph.D. thesis related to SOLA tomography (M.Sc. thesis & postdocs on SOLA tomo not listed here):

  • Ouattara, Y., 2019, University of Strasbourg/Abidjan
  • Dubois, F., 2020, University of Strasbourg
  • Latallerie, F., 2022, University of Strasbourg
  • Restelli, F., 2023, University of Royal Holloway/Oxford
  • Amiri, S., 2023, University of Strasbourg/Iran
  • Freissler, R., work in progress, University of Munich (LMU)
  • Serra, F., work in progress, University of Strasbourg
  • Mag, A., work in progress, University of Oxford
  • Schneider, A., work in progress, University of Munich (LMU)  

Example of SOLA tomography:

  • Global tomographic model SOLA-Z16 — available on SubMachine (web-based tools for exploring models).
  • This image (HAL), of SOLA-Z16, shows 3-D positive S-wave velocity anomalies (%) in mid lower-mantle: