Possible deep connection between volcanic systems evidenced by sequential assimilation of geodetic data

Area of Science:

• Volcanology
• Geophysics
• Geodesy

Background:

• Deep connections between volcanoes are typically inferred from eruptive or geochemical correlations.
• Monitoring deep volcanic system dynamics and interferences using geodetic data is challenging due to limitations in tracking transient processes.

Purpose of the Study:

• To investigate potential interplay between Grímsvötn and Bárðarbunga volcanic activities using geodetic data.
• To demonstrate the utility of sequential data assimilation for understanding deep volcanic system dynamics.

Main Methods:

• Application of a sequential data assimilation technique, the Ensemble Kalman Filter, to ground displacement data.
• Utilizing a two-reservoir dynamical model for the Grímsvötn plumbing system with fixed geometry and constant magma properties.

Main Results:

• A significant drop (up to 85%) in basal magma inflow beneath Grímsvötn was observed in the 10 months preceding the Bárðarbunga rifting event.
• A loss of at least 0.016 km³ in Grímsvötn's magma supply is interpreted as magma accumulation beneath Bárðarbunga.
• This accumulated magma likely fed the Holuhraun eruption, located 41 km away.

Conclusions:

• Sequential assimilation of geodetic data provides insights into the deep roots of volcanic systems.
• This technique holds potential for improving volcanic eruption prediction by understanding magma transfer between systems.