USTC Researchers Use Machine Learning Simulations to Confirm Earth's Core Is Leaking

A team of geoscientists from the University of Science and Technology of China in Hefei used machine-learning-boosted path-integral simulations in a Science Advances study to analyze the quantum transport of hydrogen inside Earth, finding evidence of ongoing chemical exchange between the planet's core and mantle over 4.5B years. The simulations showed that mineral-melt fractionation during early magma ocean crystallization was too weak and chaotic to sort deuterium and hydrogen, producing a homogeneous primitive mantle even with initial water content estimated at up to two ocean masses. Ocean island basalts erupting in locations such as Baffin Island in Nunavut, Canada, and Iceland show lowered deuterium-to-hydrogen ratios alongside elevated primordial helium-3 to helium-4 ratios and core-sequestered tungsten isotopes carried upward by deep mantle plumes. As light hydrogen trapped since the Solar nebula escapes upward from the molten core, it enriches the mantle and turns into water trapped within minerals in the mantle and crust. "These findings suggest that even if primordial deep-mantle reservoirs once existed, the hydrogen isotope signatures in the present-day deep lower mantle are unlikely to represent simple relics of early differentiation," — University of Science and Technology of China researchers.