New research by Spanish researchers across three continents, including SRAP-IEAP member Teresa Ubide Garralda (The University of Queensland) who is the lead author of this study, has revealed new information on how volcanoes work, and what prompts them to erupt.
The volcanoes we see on the surface of Earth are just the tip of the iceberg. Inside, they are composed of complex networks of conduits and reservoirs that feed magma (molten rock) to the surface.
Panorama of El Golfo, El Hierro island, Canary islands, Spain. Credit: Dr Laura Becerril.
The new data show that in its journey through the volcano plumbing system, the magma becomes filtered to a ‘tipping point’ that is most likely to erupt. This happens when the gas pressure builds up and propels the magma to the surface, a bit like opening a bottle of champagne.
This means that the detection of magma at this tipping point via earthquakes can indicate an upcoming eruption. This is exactly what happened before the last eruption in the Canary islands in Spain, the submarine eruption at El Hierro in 2011-12.
Tanganasoga volcano, El Hierro island, Canary islands, Spain. Credit: Dr Laura Becerril.
The study uses new analyses on lavas from El Hierro island and compares them to other ocean island volcanoes around the world, with similar results. This suggests that the volcano filtering mechanism controls eruptions in ocean island volcanoes globally.
The work has been published in the journal Geology (https://doi.org/10.1130/G49224.1).
Citation: Ubide T, Larrea P, Becerril L, Galé C, 2021. Volcanic plumbing filters on ocean-island basalt geochemistry. Geology, doi: 10.1130/G49224.1.
Teresa has also published in The Conversation (Australia) an article about this research today, and another (in Spanish) in The Conversation (España).