Description du sujet de thèse

Determine the maximum water solubility of very deep mantle minerals.
This solubility determines the conditions for mantle melting by dehydration. We will study the behaviour of water when minerals are carried away by convection movements in the mantle, and therefore the coupling between internal dynamics and the global water cycle. With this strategy, we will be able to quantify the total quantity of water “on Earth” today.

We will use the diamond cell coupled with laser heating to reproduce the internal conditions right down to the core. The microstructure and water content of the minerals will be characterised using the most advanced analytical methods. We will provide new constraints on the water retention capacity of the mantle of telluric planets, as a function of their dynamic history. The definition of behavioural laws could open up new discussions on water in the interior of Venus and a variety of exoplanets.

Contexte de travail

The experimental petrology team comprises some 15 permanent researchers and is equipped with a full range of experimental devices, including controlled-atmosphere furnaces, piston-cylinders, multianvil presses and diamond anvil cells. In addition, the laboratory has various analytical facilities such as an electron microprobe, scanning electron microscope (SEM), laser ablation mass spectrometry (LA-ICP-MS), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy.
The recruited PhD student will work within the LMV's experimental petrology team 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 (streetcar + bus)
- 44 days vacation / RTT per year

Contraintes et risques

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