Scientists have uncovered evidence of a vast natural hydrogen system deep beneath the Pacific Ocean, a discovery that could one day provide a new source of clean energy.
The find was made by researchers from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) and their international collaborators, who published their results in Science Advances.
The team explored an area on the east Caroline Plate, just west of the ancient Mussau Trench.
Unlike active tectonic boundaries where most hydrothermal vents are found, the Mussau Trench has been geologically inactive for about 25 million years.
Yet here, researchers identified a huge cluster of cylindrical geological structures, which they named the Kunlun pipe swarm.
The pipes are massive, measuring between 450 and 1,800 meters wide.
Within them, the scientists discovered signs of ancient hydrogen-rich hydrothermal activity.
Fluids carrying dissolved minerals were seen escaping through cracks, gaps, and small channels in the rock. Much of the rock is coated in yellowish material, thought to be microbial mats—layers of microorganisms that once thrived on the chemical energy from the hydrogen.
The ecosystem surrounding the pipes is also striking. Species such as scorpionfish, the top predators in this environment, were found around the Kunlun system.
Because predators depend on a large base of prey, scientists expect significant amounts of microbial life to be hidden within the breccia piles at the bottom of the pipes.
Seismic monitoring revealed more than 800 small earthquakes in just 28 days across the trench area. These tremors suggest that gas, likely hydrogen, is still actively leaking from the system today.
The scale of the Kunlun pipes is extraordinary. Their steep walls, debris piles, and multiple crater-like depressions resemble kimberlite pipes—volcanic structures formed by powerful underground explosions.
Energy calculations indicate that creating pipes of this size would have required forces equivalent to millions of tons of TNT. Hydrogen, which releases enormous amounts of energy when compressed or when reacting with oxygen, is the most likely driver of these explosions.
For example, just one ton of hydrogen gas, when compressed and then allowed to expand under the ocean’s pressure, can release as much energy as nearly a quarter-ton of TNT.
If combined with oxygen, the energy output is far greater—around 150 times higher than expansion alone. Such figures point to enormous volumes of hydrogen being stored deep in the oceanic mantle.
“This discovery suggests that a potentially huge amount of hydrogen may exist in the Earth’s lithospheric mantle,” said Prof. Xiao Yuanyuan, lead author of the study. “It could even be economically mineable in the future.”
If proven viable, this discovery could open up an entirely new frontier in the search for sustainable energy—turning the depths of the ocean into a source of clean hydrogen fuel.
