Geophysical insights into natural hydrogen potential from the exploration of ophiolitic structures in northwest Saudi Arabia

The study investigates the potential for natural hydrogen accumulations in Saudi Arabia, focusing on two ophiolitic suites in the northwestern region. The presence of ophiolitic ultramafic rocks, particularly serpentinites, makes this area promising for hydrogen generation. Airborne magnetic data were analyzed using edge-detection algorithms to delineate tectonic structures and generate a lineament density map. Moreover, 3D geophysical modelling was applied to study the geometry of the ophiolitic masses at depth and their areal extent. Lineament analysis revealed areas conducive to rainwater infiltration, which can create aquifers within the ophiolitic rocks. This infiltration is crucial for serpentinization, a reaction essential for hydrogen generation, typically occurring at temperatures above 200°C. The generated 3D models show how ophiolitic masses extend to considerable depths, highlighting fractured areas ideal for hydrogen generation and subsequent upward migration. The findings emphasize the integration of geological information with geophysical data to enhance future hydrogen exploration efforts in Saudi Arabia, and can be used as an exploration guide for similar regions with thick sediment covers over the Arabian Shield, which may serve as potential traps for hydrogen accumulation.