Glauconite and ferric illite authigenesis in marine settings as a source for geologic hydrogen

Reverse weathering, leading to the origin of authigenic glauconitic minerals, takes place today in a wide range of environments, across latitudes, and the evidence for the process has been documented in the rock record since early Proterozoic times.Here we show through mass balance equations that the formation of glauconite and ferric illite on different substrates generates a substantial amount of geologic hydrogen, almost 1-2 molar times the glauconitic minerals.Therefore, such authigenesis can add significantly to the global geologic hydrogen resources.