University of Science and Technology of China researchers find hydrogen leaking from Earth’s core

Researchers from the University of Science and Technology of China in Hefei reported on 2026-10-18 that hydrogen is leaking from Earth’s core.

Early Earth was a molten planet covered by a global lava ocean that released deadly gases. It was bombarded by fiery space debris during the Solar System’s turbulent formation. Over the following 4.5 billion years Earth cooled, allowing humans, lemurs and other life to appear.

The Earth’s core is as hot as the surface of the Sun. Early Earth’s chaotic conditions prevented orderly sorting of deuterium (a heavy isotope of hydrogen) and hydrogen through its layers.

Researchers from the University of Science and Technology of China in Hefei used machine‑learning‑boosted path‑integral simulations (a computational method that models quantum behavior) to study hydrogen movement from the core. They measured the deuterium‑to‑hydrogen ratio (the relative amount of heavy hydrogen to normal hydrogen) to detect light hydrogen leaking upward from the core.

Magma ocean crystallization (the solidification of a global molten rock layer) produces a mantle (the layer between Earth’s core and crust) whose hydrogen isotope composition is uniform, regardless of pressure, temperature or model assumptions. The starting hydrogen isotope composition of the magma ocean dominates mantle D/H distribution. Initial water content estimated at up to two ocean masses had little influence on the mantle D/H ratio.

Ocean island basalts from Baffin Island in Nunavut, Canada, and from Iceland show evidence of material upwelling from the core‑mantle boundary (the border between Earth’s core and mantle). These basalts contain light hydrogen originating from the solar nebula (a cloud of gas and dust from which the Solar System formed), a geochemical time capsule older than any known solar system material. Higher helium‑3 (a light isotope of helium) to helium‑4 (the common isotope of helium) ratios in ocean island basalts indicate the escape of primordial helium‑3 from the core.

As hydrogen escapes from the core, it enriches the mantle and lowers its deuterium‑to‑hydrogen ratio. The combined hydrogen, helium and tungsten signatures form a chemical cocktail that reveals ongoing core‑mantle exchange (the flow of material between Earth’s core and mantle) throughout Earth’s history. Researchers conclude that present‑day deep mantle hydrogen isotope signatures reflect dynamic modification by ongoing core‑mantle exchange, not mere relics of early differentiation. Tungsten isotopes (different forms of the element tungsten), initially locked in the core during planetary differentiation, are now carried upward by rising plumes, tracing core‑mantle exchange.

The study detailing these findings was published in the journal Science Advances. The ScienceAlert article reporting the research was published on 2026-10-18.