Paroxysmal eruptions tracked by variations of helium isotopes: inferences from Piton de la Fournaise (La Réunion island)

Helium isotopes (³He/⁴He) serve as a critical indicator of mantle dynamics and volcanic activity, offering potential warnings for paroxysmal eruptions. A study on Piton de la Fournaise volcano in La Réunion revealed that the highest enrichment in primordial helium (³He) correlates with the most voluminous eruptions, including caldera collapse events. This suggests a greater contribution of primitive mantle plume components during such eruptions. The research compared ³He/⁴He signatures in volcanic gases and fluid inclusions from 1990 to 2017, demonstrating analogous temporal variations even within the same eruption. These findings highlight helium isotopes as early markers for increased deep magmatic contributions, with implications for volcanic hazard assessment, as seen in both Piton de la Fournaise (2007) and Kilauea (2018).

Boudoire, G., Rizzo, A. L., Arienzo, I., & Di Muro, A. (2020). Paroxysmal eruptions tracked by variations of helium isotopes: inferences from Piton de la Fournaise (La Réunion island). Scientific Reports, 10(1). https://doi.org/10.1038/s41598-020-66260-x