Mobility and reactivity of native H2 in a West Australian basin

It is now established that molecular hydrogen (H2) exists naturally on the planet in the form of diffuse or continuous emanations. However, many questions remain unanswered as to its origin, formation mechanisms and real potential for exploitation. Recent work carried out by IFPEN and others has enabled us to precisely identify a series of mineral reactions generating the production of natural H2 at the heart of continents, in Precambrian sedimentary rocks. In Australia, Brazil and South Africa, the presence of numerous surface H2 emanations in the vicinity of Banded Iron Formations (BIFs) suggests their mineralogy plays a part in the H2 generation mechanism. However, while the nature of the "source rocks" is now constrained, questions remain as to the circulation pathways of H2 in the subsurface, and the chemical and biological reactions that will transform and consume this H2 as it rises to the surface, as well as its potential accumulation in a reservoir when and if it exists. These questions are central to the assessment of the natural H2 resource in the subsurface, because while it seems to be generated much more rapidly than hydrocarbons, this is also the case for its degradation in the subsurface. In an attempt to answer these questions, the thesis work will be structured around 3 axes: (1) structural analysis of outcrops and wells to better understand the H2 migration path (20% of the thesis ): definition of the geometric properties of faults (orientation, density, opening) and associated mechanical behavior; (2) acquisition of rocks and fluids, measurement and geochemical and mineralogical characterization of samples (30% of the thesis): He/H2 ratio, mineral oxidation rate, dissolved volatile fatty acids as a function of depth (3) basin modeling based on data collected at different scales (50% of thesis). This thesis will benefit from the expertise of CSIRO geologists based in Perth, Western Australia, who will also facilitate access to outcrop and well sampling sites. Part of the PhD will be conducted in Australia, on the field and in CSIRO’s labs in Perth.

Keywords: native hydrogen ; fluid-rock interactions ; précambrian crust ; modeling

• Academic supervisor    Prof. Eric DEVILLE, IFP School, ORCID : 0000-0002-5908-5796
• Doctoral School    ED 398, Géosciences, ressources naturelles et environnement, Sorbonne-Université
• IFPEN supervisor    Dr Olivier SISSMANN, olivier.sissmann@ifpen.fr , ORCID : 0000-0001-9372-1779 
• PhD location    IFPEN, Rueil-Malmaison (Paris), France  
• Duration and start date    3 ans, début au cours du quatrième trimestre 2024 (4 novembre)
• Employer    IFPEN
• Academic requirements    University MSc in Earth Sciences 
• Language requirements    English level B2 (CECR)    
• Other requirements    Basics in geology, mineralogy, numerical modeling 

To apply, please send your cover letter and CV to the IFPEN supervisor indicated below.