H2 migration primarily occurs along faults and fractures within the Earth's crust, which act as conduits for its upward transport from deep-seated sources Fig. 5.1. Research has demonstrated that H2 concentrations are frequently associated with fault systems, manifesting in distinct geological structures such as the “fairy circles” documented globally. A notable example is the Darling Fault in northern Western Australia, where H2 accumulations exemplify the direct link between deep fault zones and H2 occurrence. Hydrothermal systems also play a critical role in H2 migration, as elevated geothermal gradients promote the circulation of H2-enriched fluids. Furthermore, tectonic processes interacting with local geology govern the pathways and efficiency of H2 migration (Wei in Natural Gas Geoscience 35:1113–1122, 2023;Maiga in Scientific reports 13:11,876–11,876, 2023;). In the Mali region, H2 migration dynamics are influenced by fracture density, porosity variations, and the structural architecture of dolerite formations, facilitating its ascent from deep-seated origins to shallower reservoirs (Fig. 5.2) (Maiga in International Journal of Hydrogen Energy 50:640–647, 2024).