Volcanic eruptions are often preceded by magmatic dike intrusions, which manifest themselves in ground deformation, increased seismicity and changes in gas emissions as observed before the 2000 Miyake-jima (Japan), the 2018 Kilauea (Hawaii, USA), as well as the 2014-15 Bárðarbunga-Holuhraun and the 2021-24 Reykjanes Peninsula (Iceland) eruptions5,6,7,8,9,10. Monitoring these precursors is critical for detecting volcanic unrest, assessing hazards and providing early warnings of eruption-related hazards.