Ground deformation reveals the scale-invariant conduit dynamics driving explosive basaltic eruptions

Area of Science:

• Volcanology
• Geophysics
• Earth Sciences

Background:

• Basaltic volcanoes exhibit mild activity punctuated by sudden, violent explosive eruptions.
• Predicting these explosive events is challenging due to a lack of obvious precursors.
• Understanding short-term conduit processes is crucial for forecasting volcanic hazards.

Purpose of the Study:

• To investigate the minute-scale conduit processes driving violent volcanic eruptions.
• To analyze short-term ground deformation patterns preceding explosive events at Stromboli volcano.
• To develop a model explaining the source processes of sudden volcanic blasts.

Main Methods:

• Utilized two decades of ground deformation (tilt) records from Stromboli volcano.
• Applied a model to explain pressure build-up from rising volatile-rich magma.
• Analyzed the relationship between pre-blast ground inflation trends and eruption magnitude.

Main Results:

• Identified a common exponential ground inflation trend preceding all analyzed explosive eruptions.
• Demonstrated that pressure build-up is driven by the rapid expansion of rising magma in shallow conduits (<400m).
• Showed that the duration and amplitude of inflation scale with eruption magnitude, indicating scale-invariant dynamics.

Conclusions:

• The observed scale-invariance in pre-explosion ground deformation suggests a consistent conduit process for explosive eruptions.
• This scale-invariance may enable a new approach to short-term volcanic eruption forecasting.
• The findings provide unprecedented detail on the short-term processes governing violent volcanic events.