PhD position in Geochemistry
Starting date: 1 October 2022
Duration: 36 months
Net salary: 22 k€/year
General context:
We are seeking a candidate for a PhD thesis project entitled “Critical trace elements in major minerals for exploration and sustainable exploitation of metal resources: Experimental, spectroscopic and modeling study in the system pyrite-magnetite-hydrothermal fluid” to be started in October 2022.
The project aims to experimentally measure the partitioning between a hydrothermal fluid and pyrite or magnetite of a set of selected trace metals, and to study their speciation (redox state, structural position) in these two minerals, which are ubiquitous in most types of metal hydrothermal ore deposits. The new data will serve to establish predictive models of metal partitioning and uptake by these minerals as a function of key fluid parameters (temperature, pH, redox, sulfur, arsenic and salt content). These models will be used for interpreting the trace metal signatures in natural pyrite and magnetite to help reconstruct metal sources and ore deposit conditions and elaborate new ways for the prospection and extraction of critical metals.
The thesis work will use a combined approach: 1) Hydrothermal reactor experiments in Toulouse at controlled laboratory conditions to measure solubility and partitioning of metals in the system “hydrothermal fluid/pyrite/magnetite” to 700°C and 4 kbar, coupled with a range of analytical techniques available both in Toulouse and Quebec (SEM, EPMA, LA-ICPMS, ICP(QQQ)MS, TEM). 2) The chemical speciation and redox state of metals in fluids and synthetic minerals will be characterized using high-resolution X-ray absorption spectroscopy at the European synchrotron (ESRF). 3) Physical-chemical modelling, using both thermodynamic and ab-initio structural simulations, of the speciation and partitioning of the metals between fluid and mineral, which would be transposable to natural hydrothermal contexts. We will attempt to propose, for the first time in ore deposit research, a quantitative physical-chemical and geochemical interpretation of patterns of the trace elements in natural pyrite and magnetite from various hydrothermal contexts.
The work will be carried in part within the framework of French-Canadian collaborative project FFCR “CRITRACE: Critical trace elements for mineral exploration and sustainable exploitation of metal resources”, between the GET laboratory (CNRS, University de Toulouse, resp. Gleb Pokrovski) and the University Laval (resp. Georges Beaudoin), by benefiting the synergy of the complementary expertise of the two teams (Toulouse: experimental, physical-chemical and spectroscopic approaches for studying fluids and minerals; Quebec: prospection of metal deposits and analytical and geochemical methods for characterizing mineral resources). The work will benefit from an interdisciplinary environment, with additional collaborations with INEEL/ESRF (Grenoble), ENS/IMPMC (Paris), and University of Geneva laboratories, offering complementary expertise and facilities. The PhD student will receive a high-quality education and training in the field of experimental and analytical geochemistry, in situ spectroscopic techniques, physical-chemical modeling and economic geology.
Prerequisites:
The applicants should hold a Master degree in Geology, Chemistry or Physics by July 2022. We seek for a highly motivated person, particularly interested in ore deposit geochemistry, hydrothermal processes and physical-chemistry in general, and enjoying laboratory experimental, analytical and modeling work. The candidate should, in addition, have a sufficient background in aqueous/inorganic chemistry and thermodynamics. The candidate should be comfortable in English. Knowledge of French is not in principle mandatory at start, but the candidate will be expected to learn the spoken and written French during the thesis work.
Application:
The candidates should submit, in a single pdf file by email, a statement of research experience, interests, and motivations concerning this PhD project, a detailed CV including the complete list of education records and classifications (L3, M1 and M2), and the names and contact information of two potential referees to: Dr. Gleb Pokrovski, Cette adresse e-mail est protégée contre les robots spammeurs. Vous devez activer le JavaScript pour la visualiser., phone: (+33)561332618. Please contact Dr. Pokrovski for additional information concerning the project. Mode details (in French) about the thesis work and the Doctoral School can be found at http://sdu2e.obs-mip.fr/ . General information about the GET laboratory is available at: https://www.get.omp.eu/ .
The selected candidates will be evaluated and interviewed in June 2022 by the Doctoral School committee SDU2E of the University of Toulouse. The obtaining of this PhD fellowship is primarily conditioned by the student’s education records and grades and performance during the interview.
