173-3 Natural Hydrogen Occurrences in Northwest Morocco: Evidences from Soil Gas Surveys and Subsurface Data.

Session: Geologic Energy Resources and Storage for Now and the Future

Presenting Author:

Ismail ES-SABBAR

Authors:

ES-SABBAR, Ismail¹, TOUBRI, Youssef², RAJI, Otmane³, BERKAT, Nour Eddine⁴, OUABID, Muhammad⁵, EL BAROUDI, Majid⁶, ENNABBADI, Reda⁷, SADKI, Othman⁸, BENZAAZOUA, Mostafa⁹

(1) Geology and Sustainable Mining Institute, Mohammed VI Polytechnic University, Benguerir, Morocco, (2) Geology and Sustainable Mining Institute, Mohammed VI Polytechnic University, Benguerir, Morocco, (3) Geology & Sustainable Mining Institute, Mohammed VI Polytechnic University, Benguerir, Morocco, (4) Office National des Hydrocarbures et des Mines, Rabat, Morocco, (5) Geology & Sustainable Mining Institute, Mohammed VI Polytechnic University, Benguerir, Morocco, (6) Geology & Sustainable Mining Institute, Mohammed VI Polytechnic University, Benguerir, Morocco, (7) Office National des Hydrocarbures et des Mines, Rabat, Morocco, (8) Office National des Hydrocarbures et des Mines, Rabat, Morocco, (9) Geology and sustainable mining institute, Mohammed VI Polytechnic University, Benguerir, Morocco,

Abstract:

In the global effort to reduce carbon emissions in line with the Net-Zero Emissions by 2050 initiative, increasing attention is being directed toward cleaner energy alternatives. Recently, natural hydrogen (H₂) has emerged as a promising candidate for energy transition. Exploration efforts for this resource are gaining momentum and are guided by specific geological and morphological indicators. Among these, sub-circular depressions (SCDs) have garnered growing interest as potential proxy for H₂ exploration. To evaluate their relevance in H₂ exploration, it is essential to situate them within a robust geological and geochemical framework, supported by detailed subsurface investigations. In Morocco, numerous SCDs clustered in the Rabat-Khemisset region exhibit a suspected potential for geological exploration of natural H₂ occurrences. Mapping these structures using satellite imagery revealed their abundance across the study area, specifically in the southwestern part. Morphologically, these SCDs appear to be confined to flat areas characterized by unconsolidated, soft sediments. Soil gas survey conducted on 33 depressions revealed elevated H₂ concentrations, with some measurements reaching up to 1000 ppmv. Notably, the highest concentrations were consistently recorded at the margins of the depressions. Integration of seismic profiles and borehole data suggests that the spatial distribution of SCDs is primarily associated with areas where the basement is shallow. Moreover, the distribution of SCDs appears to be influenced by the presence or absence of effective sealing lithologies. This is evidenced by the high density of SCDs in the Maamora and Sidi Bettache basins, which coincides with areas lacking seal formations. In contrast, their scarcity in the Gharb and Khemisset basins is likely attributed to the presence of the Rifan nappe and thick sequences of clay and evaporites, which may act as effective flow barrier. Additionally, the alignment of numerous SCDs with major fault systems in the Maamora region and northern Sidi Bettache Basin suggests a potential structural control on their spatial distribution. This study confirms the occurrence of H₂ seepage associated with SCDs and provides a basis for further investigations into the potential H₂ system.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-6290

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