Inflation-predictable behavior and co-eruption deformation at Axial Seamount

Area of Science:

• Volcanology
• Geophysics
• Marine Geology

Background:

• Ground deformation at volcanoes indicates subsurface magma movement.
• Axial Seamount's eruptive activity is linked to magmatic pressure and inflation.

Purpose of the Study:

• To analyze seafloor deformation data to understand magma supply and eruptive predictability at Axial Seamount.
• To document the first real-time capture of volcanic deflation and tilt using a seafloor cabled observatory.

Main Methods:

• Analysis of seafloor deformation measurements from 2011-2015.
• Real-time monitoring of volcanic activity using a new seafloor cabled observatory.
• Deformation modeling to identify the subsurface pressure source.

Main Results:

• A fourfold increase in magma supply was detected between 2011 and 2015.
• The 2015 eruption was successfully forecast based on deformation patterns.
• The observatory captured real-time deflation and tilt, detailing eruption dynamics.
• Modeling indicated a steeply dipping prolate-spheroid pressure source beneath the eastern caldera.

Conclusions:

• Axial Seamount's eruptions are inflation-predictable, likely triggered by critical magmatic pressure.
• Real-time seafloor observatories are effective tools for monitoring and forecasting volcanic eruptions.
• Subsurface deformation data and modeling provide insights into magma reservoir structure.