Context and work environment
Structure description: The PhD will be hosted at the Laboratoire Interdisciplinaire de Physique (LIPhy, Université Grenoble Alpes/CNRS), in Grenoble, and carried out in close collaboration with the Institut des Sciences de la Terre (ISTerre, Université Grenoble Alpes/CNRS).
Team description: The researcher will join the MODI team (Soft Matter, Organization, Dynamics and Interfaces) in LIPhy, under the supervision of Elsa Bayart and work with the Fault Mechanics and Instabilities team at ISTerre, under the supervision of David Amitrano and Jérôme Weiss.
This recruitment takes place within the PhD@Tec21 Programme, which is co-funded as part of the Marie Skłodowska-Curie COFUND actions under the grant agreement #101217261. The recruitment process follows a specific selection and evaluation procedure with particular eligibility criteria, all of which are detailed in the applicant guide available on PhD@Tec21 Website.
Mission and main activities
Laboratory Characterization of Seismic Ruptures: Linking Local Fault Mechanics to Seismic Observables
Description of the project: Earthquakes occur when faults suddenly slip and release accumulated stress. Understanding how this slip starts, propagates and radiates seismic energy is essential for earthquake physics and for improving seismic hazard assessment. In natural earthquakes, source parameters such as rupture length, stress drop and radiated energy are inferred from remote seismic measurements.
Laboratory experiments offer a unique opportunity to overcome the lack of direct access to fault-scale rupture processes in natural earthquakes. They allow physical quantities to be measured directly on or near the fault while simultaneously acquiring non-local acoustic data, enabling direct validation of the relationships between local fault-scale parameters and seismic observables.
Here, we propose to establish a quantitative link between local fault mechanics and seismic observables, using a laboratory fault that generates seismic-like ruptures along a controlled heterogeneous granular interface. The experiment will combine direct measurements of strain fields and particle displacement fields on and around the fault with simultaneous acoustic-emission recording. These datasets will allow us to rigorously test models used to infer source parameters from acoustic-emission records, such as estimating the static stress drop from the waves frequency content.
Possible research axes:
- Connecting rupture mechanics and seismic magnitudes. Compare magnitudes estimated from local deformation and slip with magnitudes derived from emitted acoustic waves; explore how rupture geometry, heterogeneity and measurement uncertainties contribute to event-to-event variability.
- Testing seismic inversion models and stress drop scaling. Use broadband acoustic spectra to infer source parameters, in particular static stress drop and rupture length, confront these estimates with direct mechanical measurements, and examine the dependence of stress drop with event magnitude.
- Understanding rupture nucleation and precursory activity. Combine grain-resolved imaging, local mechanical measurements and high-sensitivity acoustic detection to investigate aseismic pre-slip, foreshock cascades and foreshock/aftershock statistics, including the influence of detection thresholds.
The experimental and analysis strategy will be adapted to the candidate’s background and interests. The thesis may emphasize one or two axes, while contributing to a shared experimental framework.
Supervisors: David Amitrano, Elsa Bayart and Jérôme Weiss
Research fields: Experimental mechanics; friction and fracture; earthquake physics; seismological models; acoustic emission; quantitative signal and image analysis.
Possible secondments (industrial or academic partners): Department of Mathematics & Physics, Università della Campania "Luigi Vanvitelli" (IT)
Doctoral school: IMEP² (Engineering – Materials, Mechanics, Environment, Energy, Processes, Production).
Desired profile and expected skills
Education, diplomas
Master’s degree (or equivalent) in physics, geophysics, mechanics, materials science, engineering, or a closely related discipline.
Disciplinary skills, experience
Solid background in physics or related disciplines, with an interest in solid mechanics and in Earth sciences. Experience in experimental work is necessary. Acoustic/signal analysis and image analysis ability will be acknowledged. Knowledge of at least one scientific programming language is necessary (e.g., Python/Matlab/C++). Ability to communicate scientific results in English.
Personal skills
- Strong interest in interdisciplinary research, with a willingness to work at the interface between different scientific fields
- Enthusiasm for experimental work, with a rigorous and careful approach to measurements and data analysis.
- Willingness to openly discuss research progress, share results as well as difficulties, and collectively seek solutions to scientific and technical challenges.
- Active participation in the scientific life of both laboratories (group meetings, seminars, scientific discussions, etc.) is expected.
Employment benefits and conditions
Université Grenoble Alpes (UGA) is offering a 36-month full-time work contract.
In line with the European Commission rules for Marie Skłodowska-Curie grant holders, the remuneration will consist of a gross monthly salary of 2,650 EUR. The estimated net salary to be perceived by the PhD fellow will be between 2,050 and 2,150 EUR.
Benefits include:
- Access to a high-quality work environment, including a personal computer, scientific equipment and access to library and shared lab facilities
- Access to high-level scientific and inter-sectoral training through 120 hours of doctoral courses and workshops
- Opportunity for 2-month secondments at an academic institution or industrial partner during the 2nd year of the PhD
- A vast choice of networking events and activities within the PhD@Tec21 Programme and through the international network of MSCA fellows
- Access to the UGA International Student Office, to assist the PhD fellows in searching for accommodation in Grenoble and support with administrative issues including visas, health, bank accounts, etc.
- Visa fees and registration to the UGA Doctoral School are covered by PhD@Tec21
- 45 days of paid holidays
- Sick leave
- Parental leave
General information
Contact for the questions related to the position:
PhD@Tec21 Management Board:
guillaume.chambon@univ-grenoble-alpes.fr / amelie.bataille@univ-grenoble-alpes.fr
