Global Hydrogen Occurrences and Field Observations
Hydrogen outgassing in ophiolite systems
This study documents significant hydrogen emissions from the Zambales ophiolite complex in the Philippines where the highest measured hydrogen flux from ophiolites has been documented to date. Providing new field evidence for hydrogen generation associated with ultramafic rocks undergoing serpentinization, this study combines field measurements with geological interpretation, highlighting the importance of tectonic structures and rock composition in controlling hydrogen flux to the surface. The results reinforce the role of ophiolite belts and ultramafic terrains as potential hydrogen source regions and provide valuable field analogs for exploration strategies worldwide.
Professor Emmanuel Codillo of the Stanford Geologic Hydrogen IAP continues to investigate this region because of its close spatial association with chromite-rich rocks. He is currently investigating whether chromite plays a catalytic role in hydrogen generation and what factors control high outgassing in this area.
Soil geochemistry of hydrogen along the San Andreas Fault
This study kicked off Stanford’s investigation of geologic hydrogen in 2021! It demonstrated the use of soil gas geochemistry as a tool for identifying hydrogen anomalies associated with active fault systems. Extensive soil gas sampling across the San Andreas Fault system revealed hydrogen concentrations significantly above atmospheric levels and strongly correlated with fault structures. Statistical analysis of the gas data identified distinct geochemical clusters and potential end-member gas sources, suggesting that serpentinization and tectonic activity may both contribute to hydrogen generation. The research highlights how surface geochemical surveys can serve as a practical exploration method for detecting subsurface hydrogen systems.
Field investigations at Salton Trough (New!)
The Salton Trough of southern California is a promising geological setting for investigating geologic hydrogen systems. Located within the actively rifting boundary between the Pacific and North American plates, the basin combines high heat flow, extensive faulting, and active fluid circulation—conditions favorable for hydrogen generation through water–rock reactions such as serpentinization. Ultramafic and mafic rocks associated with the region’s complex tectonic history may provide iron-rich source materials capable of producing hydrogen, while the area’s geothermal systems demonstrate that deeply circulating fluids interact with hot crustal rocks and migrate through permeable fault networks. These structures may serve both as pathways for hydrogen migration and as sites where tectonic activity continually exposes fresh mineral surfaces that can promote hydrogen generation. In addition, decades of geothermal exploration and drilling in the Salton Sea region provide an unusually rich subsurface dataset—including well logs, fluid compositions, and temperature profiles—that can help constrain hydrogen system models. For these reasons, together with the USGS, the Stanford Geologic Hydrogen Consortium is initiating field investigations in the Salton Trough to evaluate its hydrogen prospectivity and to test exploration methods for identifying active hydrogen-generating systems in tectonically dynamic basins.