Description du sujet de thèse

To determine the behaviour of noble gases during the early stages of the Earth's accretion and the segregation of its core. Complementary experiments will be carried out at ESRF (under the supervision of Angelika Rosa) and in Paris in collaboration with Julien Siebert and Ingrid Blanchard.
The candidate's main activities will be as follows:
- Development of metal-silicate separation experiments with rare gases at high pressure and high temperature using the laser-heated diamond-anvil cell technique.
- Chemical analysis of the products obtained.
- Geochemical modelling.
Two major objectives have been defined for this thesis project:
1- Determination of metal-silicate partition coefficients for noble gases under deep magmatic ocean conditions (from 25 to 75 GPa; 2500 - 3500 K; and an oxygen fugacity of between IW-2 and IW-5). Note that the initial chemical compositions will contain volatile elements (C, H, N, O, S).
2- Determining the rare gas content of the Earth's core and the silicate part of the Earth.

Contexte de travail

Laboratoire Magmas et Volcans is located in Clermont-Ferrand, in central France. This region offers excellent opportunities for outdoor activities and has a low cost of living. The experimental petrology team consists of about 15 tenured researchers and is equipped with a comprehensive range of experimental devices, including one-atmosphere furnaces, EHPV (End-Hydrostatic Pressure Vessel), IHPV (Intermediate Hydrostatic Pressure Vessel), piston-cylinders, multi-anvil presses, and diamond-anvil cells. Additionally, the laboratory features various analytical facilities such as an electron microprobe, scanning electron microscope (SEM), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy.
The recruited PhD candidate will work as part of the Experimental Petrology team at the LMV and will benefit from:
- A stimulating work environment in contact with research staff
- Professional support with in-house training
- Partial reimbursement of travel expenses (75%)
+ sustainable mobility package of up to €300/year
- A site accessible by public transport (Tram + bus)
- 44 days vacation / RTT per year

Contraintes et risques

Safety rules must be observed every time the instruments are used.