ISTerre seminar

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Defining pathfinders for hydrogen exploration

Thursday 13 March 2025 - 11h00

L. Truche, B. Malvoisin - ISTerre
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Hydrogen (H2) plays a central role in the abiotic synthesis of simple organic compounds and in supporting deep microbial communities. Furthermore, deep crustal production of H2 now represent an emerging topic of exploration because this molecule may contribute to the accumulation of potentially extractable energy resources in geological environments that have not been previously targeted by the oil and gas industry. Thus, defining exploration pathfinders and constraining H2 flux from sources to seeps is key to understanding the geologic hydrogen resource potential. The high mobility of hydrogen combined with its high reactivity, both at high and low temperatures, are supposed to prevent its accumulation in the subsurface or its concentration in geological fluids except in rare occurrences. However, this paradigm is now shifted by the recent discoveries of geological environments suitable for hydrogen trapping and of several continental zones where natural hydrogen is released. It now appears necessary to methodically and reasonably evaluate the sources, sinks, flows and stocks of this potential primary natural production. Even if the phenomena controlling the generation (redox reactions, radiolysis, fermentation), migration (solubility, clathrates, diffusion, adsorption) and reactivity (microbial or surface catalysis) of H2 in the Earth's crust are now quite well understood, their interplays remain to be unraveled. We will show how some recent observations made at ISterre from the nanoscale up to the basin scale using experimental, numerical and field approaches can provide new insights into the hydrogen system. We will then highlight the potential of some H2-fertile areas recently explored by our research group in Grenoble.

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Organizing team : Organisation labo

Amphithéâtre Killian, Maison des Géosciences, 38400 Saint Martin d'Hères