Re-evaluating Legacy Well Data for Natural Hydrogen Exploration

Natural hydrogen (H₂), also referred to as white, gold, or native hydrogen, is a geologically sourced form of molecular hydrogen occurring as free gas within the Earth's crust, including continental and oceanic lithospheres, volcanic exhalations, and hydrothermal systems. Unlike anthropogenically produced hydrogen via steam methane reforming or water electrolysis, natural hydrogen is generated in situ through ongoing geological processes such as serpentinization, radiolysis, and mantle degassing, offering a continuous, low-emission energy resource. Recent accidental detections, most notably in France’s Lorraine Basin during coalbed methane investigations, have revitalized global interest in subsurface natural hydrogen exploration. These discoveries suggest that hydrogen accumulations may have been historically overlooked in conventional hydrocarbon wells due to prior analytical limitations and the absence of targeted detection methodologies. This study proposes a systematic re-evaluation of legacy well logs from abandoned and active oil and gas wells to identify Petrophysical, Geophysical, and Geochemical signatures indicative of natural hydrogen. Preliminary evidence from regions such as Spain (Helios Aragón Project) and the United States (Koloma Inc.) supports the viability of this approach. Cost projections for natural hydrogen extraction ($0.5–$1.5/kg) indicate a substantial economic advantage over green hydrogen. Exploration activities are gaining traction in Mali, Australia, the USA, France, and other parts of the world. In India, ONGC has initiated hydrogen seep investigations in the basins of Gujarat and Assam. The primary objective of this study is to develop interpretive log-based frameworks capable of discriminating hydrogen-bearing intervals using existing datasets, thereby enabling rapid screening and derisking of prospective hydrogen-bearing reservoirs.