Deep in the Midwest, Rocks Are Brewing Clean Fuel

Scientists map serpentinization signatures in Iowa's Midcontinent Rift, giving explorers a new geophysical tool to target natural hydrogen

13 Mar 2026

Researchers have developed a geophysics-based method to identify zones of natural hydrogen generation within the Midcontinent Rift, a billion-year-old geological formation that runs beneath Iowa, Minnesota and several other US states.

The study, published in Scientific Reports in January 2026, finds that iron-rich igneous rocks beneath Iowa have undergone serpentinization, a reaction between rock and groundwater that produces molecular hydrogen. The same process forms magnetite, a magnetic mineral that creates a detectable signal in geophysical survey data.

By combining magnetic, gravity and electromagnetic datasets across Iowa’s portion of the rift, a research team from Colorado School of Mines mapped areas where serpentinization appears active or has occurred at large scale. The work suggests these zones may be capable of generating significant volumes of natural hydrogen.

The approach could provide exploration groups with a more systematic way to search for the gas, which until recently has been investigated largely through small pilot projects and limited drilling data.

Iowa’s geological survey contains only 24 borehole samples drilled to depths relevant to hydrogen exploration. As a result, much of the rift remains poorly characterised. The researchers argue that surface and airborne geophysical surveys could be used to screen wide areas before companies commit to drilling wells, reducing early-stage exploration costs.

The US Geological Survey has previously identified Iowa and the wider midcontinent region as among the most promising areas in the country for natural hydrogen accumulation.

Commercial interest has also begun to grow. Koloma, which is operating in Iowa, has described the state’s subsurface as having “very high hydrogen potential”, citing geological conditions similar to those outlined in the research.

Scientists say the method may also be applicable beyond the US. Serpentinization-driven hydrogen systems leave similar magnetic and geophysical signatures in other geological settings, including rift systems and ophiolite formations.

Natural hydrogen produces water vapour when burned and is being studied as a potential low-emissions energy source. As research advances, the Midcontinent Rift is increasingly viewed by geologists as an important testing ground for the emerging sector.