Key Discoveries
Record-Breaking Ratios: Analysis of 62-million-year-old Arctic lava rocks from Canada’s Baffin Island revealed helium-3 (³He) concentrations 70 times higher than atmospheric levels—the highest ever recorded in volcanic material. Similar anomalies were found in Icelandic lava. Primordial Origins: The ³He/⁴He ratios, along with neon isotope signatures, match conditions from Earth’s formation, pointing to a preserved reservoir of ancient noble gases. Core Leak Hypothesis: Simulations indicate helium-3 trapped in the core during Earth’s accretion is seeping into the mantle via slow chemical exchange, escaping through volcanic hotspots like Baffin and Iceland. Evidence & Methodology Isotopic Analysis: Researchers studied olivine crystals in basaltic lavas, measuring ³He/⁴He, strontium, neodymium, and neon isotopes to rule out atmospheric contamination. Mantle Plumes: Both Baffin and Iceland sit above mantle plumes—geological “hotspots” that tap deep reservoirs, enabling helium-3 to rise from the core-mantle boundary. Why Helium-3 Matters Rarity on Earth: Most primordial helium-3 escaped into space early in Earth’s history due to its lightness. Remaining surface traces imply a deep, protected source. Core as a Reservoir: Earth’s iron-rich core likely absorbed noble gases during planetary assembly. Slow leakage over eons suggests an ongoing chemical exchange between the core and mantle.RESEARCH PAPER 
F. Horton et al., “Highest terrestrial 3He/4He credibly from the core”, Nature (2023)
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