Missions

This research engineer position is part of an ANR project on the chemical alteration of faults and the dependencies between alteration and tectonic activity. This project is based on two sites characterized by drilling measurements and from which rock samples were extracted: the Nojima site in Japan from which the samples were taken after the 1995 earthquake, and the Soultz-sous-Forêt site in France exploited for geothermal purposes since the 2000s.
The rock samples are characterized by different laboratory methods (dating, X-ray imaging, micro-structural analysis, etc.) and the alteration processes are reproduced by experiments in reactive transport cells. In connection with these laboratory experiments and site observations, the objective of this postdoctoral fellowship will be to implement numerical simulations of the injection of a reactive fluid into fracture networks. This will require handling a particle tracking code developed by the research team in C++ and modifying it to account for geochemical reactions. The impact of these reactions, i.e., changes in concentrations and porosities, will be determined through geochemical simulations performed by project collaborators. The proposed work will be organized as follows: (i) familiarization with particle tracking methods by reading bibliographic references and getting familiar with the existing code; (ii) development of the conceptual model to adapt it to the geochemical problems under consideration; (iii) implementation and calibration based on experimental results.

Activités

Main tasks:
- Acquiring knowledge on particle displacement methods to simulate solute transport
- Defining a conceptual model to account for geochemical reactions
- Comparison between numerical and experimental results, and model calibration
Secondary tasks:
- Collaborating with the project's geochemists and geologists
- Restitution of the work carried out in the form of presentations at meetings and contribution to the writing of scientific publications

Compétences

- Physical understanding of flow and transport processes (Stokes/Darcy and heat/advection-diffusion equations)
- Proficiency in C++ and Python/Matlab programming languages
- Interest in developing conceptual models
- Skills in result analyzing

Contexte de travail

Geosciences Montpellier is a joint research unit (UMR5243) bringing together CNRS researchers and teacher-researchers from University of Montpellier and University of Antilles. It is attached to the Universe Sciences Mediterranean Environmental Research Observatory (OSU OREME). The workforce is approximately 160 people, including technicians, engineers, interns, PhD students and post-doctoral fellows. The mission of the laboratory is to develop new knowledge on Earth dynamics and its surface manifestations, resources and the environment, considering the couplings between different envelopes (atmosphere, hydrosphere, crust, mantle). The objectives are to improve the understanding of geodynamic processes at different scales of time and space, and to contribute to research on the characterization and management of natural hazards as well as resource management.
The proposed position will be hosted in the TMP (Transport in Porous Media) team and in the Hydrosystems and Resources research axes in connection with the Numerical Computing Platform (PCN). The supervision will be carried out by CNRS researcher in collaboration with another CNRS researcher and researchers from ISTerre (Grenoble).