Assessing Natural Hydrogen Generation in Serpentinization Environments: A Workflow Based on a Comprehensive Case Study Analysis from the HyAfrica Project

Natural hydrogen, emerging as a clean and abundant energy source, holds significant promise for advancing sustainable energy solutions. Its production offers a carbon-neutral alternative to fossil fuels, aligning with global efforts to mitigate climate change. This research focuses on developing a methodology to estimate the rates of natural hydrogen generation in serpentinization areas; in this case a local area in Eastern Morocco. It employs a multilevel approach that encompasses the modeling and analysis of the surface, near-surface, and deep components of the natural hydrogen system. At the surface level, potential hydrogen seeps are identified as semi-circular structures and surface faults are examined using high-resolution geophysical data. For the near-surface component or seal of the potential reservoir, which can extend thousands of meters deep, a full 3D geological model is constructed. The deep component, representing the source rock, is analyzed through the inversion of potential field data. These inversion results allow estimating the degree of serpentinization of the rocks, their volumes, and the affected surfaces. Subsequently, these volumes of rock are compared with temperature estimates to determine which part of the rock is capable of generating hydrogen. Laboratory-based hydrogen generation values from rock samples are then scaled up to the model, facilitating the calculation of hydrogen generation rates from the detected ultramafic rocks.