Evidence points to ongoing core–mantle exchange of primordial material

Hydrogen-transport simulations considered with isotope patterns

Researchers at the University of Science and Technology of China used machine-learning-boosted path-integral simulations to examine hydrogen transport in Earth’s interior. ScienceAlert reports that their results, together with isotope patterns involving hydrogen, helium, and tungsten, support material from the core reaching mantle plumes that form ocean-island basalts.

The reported research examined whether hydrogen-isotope differences in the deep mantle were relics of early magma-ocean crystallization or reflected chemical exchange between the core and mantle.

The researchers report that simulations of magma-ocean crystallization and hydrogen, helium, and tungsten isotope evidence from ocean-island basalts instead support ongoing core–mantle exchange. Under this interpretation, present-day deep-mantle hydrogen signatures are not simple records of early differentiation.

Deep signatures may reflect more than primordial conditions

If the reported interpretation holds, isotope signatures in the deep lower mantle would reflect continuing exchange with the core throughout Earth’s evolution, rather than only conditions left by the planet’s early magma ocean.