Défense de thèse

Soutenance de thèse de Hadrien Pirotte


Infos

Dates
18 décembre 2023
Lieu
Institut de Géologie, Bât. B18, R125
Quartier Agora - Allée du Six-Août, 14
4000 Liège
Voir la carte
Horaires
15h00

Le lundi 18 décembre 2023, Hadrien PIROTTE présentera l'examen en vue de l’obtention du grade académique de Docteur en Sciences (Collège de doctorat en Géologie) sous la direction de Bernard CHARLIER et Anne POMMIER.

Cette épreuve consistera en la défense publique d’une dissertation intitulée :

« Planet Mercury and the behavior of elements in reduced conditions ».

Abstract

Planet Mercury exhibits exotic characteristics compared to Earth. Its surface shows highly reduced lavas devoid of FeO and rich in sulfur. To understand processes that shaped the surface and the interior of the planet, we need information on the chemical behavior of elements under very reducing conditions. To that end, we performed around a hundred experiments using various experimental apparatuses, spanning a large pressure and temperature range (0.0001 – 6 GPa and 1300 – 1700 °C) on powders whose compositions are representative of Mercury’s silicate part and lavas. Based on the produced data and the literature, we modeled the distribution of elements in Mercury’s reservoirs during its differentiation and partial melting of the mantle. Thanks to these models, we infirmed the existence of an FeS layer formed in equilibrium with the silicate part, we showed that the surface experienced important K-loss, and we proposed that the mantle should host a significant amount of CaS. Finally, we showed that the value of the difference of metal-silicate partitioning between two different elements in a sample is directly proportional to their difference in electronegativity. Based on a large dataset from the literature, we propose a new equation to predict metal-silicate partition coefficients.

Lien Orbi

Le Jury sera composé de :

M. F. HATERT (Président), Mmes et MM. C. CARTIER (Université de Lorraine), B. CHARLIER (Promoteur) (Secrétaire), M. COLLINET (UNamur), O. NAMUR (KULeuven), A. POMMIER (Carnegie Institute for Science, Washington) (Co-promotrice).

 

 

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