Abstract
Natural hydrogen (H2) is a promising resource for the energy industry’s transition to zero-carbon fuels. However, its extent and feasibility for exploitation remain unclear. A key step towards discovering subsurface dihydrogen accumulations is detecting H2 seeps. This study presents the first autonomous, multi-gas monitoring of a natural hydrogen seep in Australia, where dihydrogen, carbon dioxide, and hydrogen sulphide were measured together. The research revealed significant H2 seepage on the Yilgarn Craton in Western Australia, with seasonal fluctuations: high emissions after dry summers and reduced emissions following rainfall due to increased groundwater levels. Groundwater appears to act as a seasonal inhibitor to H2 seepage through the near subsurface potentially leading to false negatives in soil gas surveys post-rainfall and in low-lying areas. This work provides fundamental data for natural hydrogen exploration and therefore aids in the implementation of a large-scale hydrogen economy.