PhD thesis in geosciences on magmas in the solar system M/F

Job Description

Thesis Subject

PhD on SPECIATION AND SOLUBILITIES OF NITROGEN, CARBON AND SULFUR IN EXOPLANETARY MAGMAS

Multiple magmatic episodes occurred during the formation of planetary bodies, and their outgassing, which formed the first atmospheric
envelopes, is the subject of a major scientific debate. Examples of this primordial magmatism include the oldest magmatic rocks, the
angrites, and fragments of glassy silicates encapsulated in chondrites, called chondrules, all dating back to the early solar system (4.5
billion years ago). We must also highlight the numerous observations of hot exoplanets close to their stars, whose equilibrium
temperatures exceed the melting point of rocks.
Cosmochemical and astrophysical observations of these extraterrestrial magmas converge on a atypical magmatism compared to that
which prevails today on Earth: Redox conditions are extremely reduced, thus pointing to the absence of free oxygen in these environments, and these systems furthermore appear to be exposed to very high hydrogen (H2) pressures. Under this exotic regime, our
knowledge of the behavior of key elements in magmatic degassing (H-C-N-S) is inadequate due to poor empirical and theoretical
foundations. For example, we do not know if it is possible to form H2S, NH3, and CH4 components in molten silicates, even though the
implications for the chemistry of degassed atmospheres would be transformative for the scientific community.
This thesis aims to fill this gap in fundamental knowledge by combining cutting-edge experimental and analytical approaches.

Your Work Environment

This PhD project will be carried out within the European GEAOSTRONOMY network, which involves 40 researchers across Europe. Eight PhD students and eight postdoctoral researchers are working on this project. Working meetings are held twice a year with this network

We will utilize the ISTO experimental platform, which allows for the laboratory synthesis of magmas exposed to these exotic conditions (high
temperature, high pressure, high hydrogen fugacity, fH2, and low fO2). We will also leverage the developments of LADYBIRD (PI Rémi
Champallier, IR at ISTO, involving engineers from ICMN and CEMHTI), an experimental project, which surpasses temperatures ever
reached experimentally under gas pressure. We will also draw upon the extensive expertise of CEMHTI (Pierre Florian, specialist in NMR
spectrometry) to characterize the speciation of gases dissolved in the silicate glasses formed in the laboratory. Finally, we will collaborate
with IPG-Paris (Jabrane Labidi, Research Scientist) and CRPG-Nancy (Laurette Piani, Research Scientist) to quantify the elemental
concentrations and isotopic signatures of H, N, C, and S in these vitreous silicates. At ISTO, a postdoctoral researcher from the
GEOASTRONOMY team, Dr. Dmitri Bondar, with extensive experience (PhD +3), will be involved in supervising the thesis.
GEOASTRONOMY, a collaborative european project, will provide half of the PhD funding as well as the funding support for laboratory and
field missions.
This PhD project is therefore highly unifying and structuring for the local and european scientific ecosystem because it synergizes the
financial resources and expertise of different laboratories. It also connects this Orléans expertise with complementary expertise from other
leading laboratories in France (IPG-CRPG). Ultimately, it provides a high-level technological and scientific environment and thus an ideal
springboard for the development of a young scientist.

The candidate must have an experience in one of the following field:
- High pressure / high temperature experimentation
- Vibrational spectroscopy on solid en dense fluid materials
- Thermodynamics of high temperature reactions
- Magmatic/hydrothermal systems

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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