EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Forecasting the fate of unrest at basaltic calderas

Valerio Acocella1, Federico Galetto2, Andrew Hooper3, and Marco Bagnardi4
Valerio Acocella et al.
  • 1Università Roma Tre, Dipartimento Scienze, Roma, Italy (
  • 2Cornell University, Department of Earth and Atmospheric Sciences; Ithaca, NY, USA
  • 3COMET, School of Earth and Environment, University of Leeds; Leeds, UK
  • 4NASA Goddard Space Flight Center; Greenbelt, MD, USA

Forecasting eruption is the ultimate challenge for volcanology. While there has been some success in forecasting eruptions hours to days beforehand1, reliable forecasting on a longer timescale remains elusive. Here we show that magma inflow rate, derived from surface deformation, is an indicator of the probability of magma transfer towards the surface, and thus eruption, for basaltic calderas. Inflow rates ≥0.1 km3/year promote magma propagation and eruption within 1 year in all assessed case studies, whereas rates less than 0.01 km3/year do not lead to magma propagation in 89% of cases. We explain these behaviours with a viscoelastic model where the relaxation timescale controls whether the critical overpressure for dike propagation is reached or not. Therefore, while surface deformation alone is a weak precursor of eruption, estimating magma inflow rates at basaltic calderas provides improved forecasting, substantially enhancing our capacity of forecasting weeks to months ahead of a possible eruption.

How to cite: Acocella, V., Galetto, F., Hooper, A., and Bagnardi, M.: Forecasting the fate of unrest at basaltic calderas, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-5317,, 2023.