The 2022 Eruption of Wolf Volcano, Galapagos: The Role of Caldera Ring-Faults During Magma Transfer From InSAR Deformation Data

The basaltic caldera volcanoes in the Galapagos Islands characteristically erupt lavas via summit circumferential and radial flank dike intrusions, but the underlying magma plumbing systems remain enigmatic. Here, we document surface displacements of Wolf volcano using interferometric synthetic aperture radar (InSAR) data from 2015 to 2022. We show that Wolf volcano experienced 6-years of continuous inflation after the 2015 eruption, followed by a shallow flank eruption in January 2022. The deformation is modeled with a vertical caldera ring-fault and a radial dike on the southeast flank. The ring-fault underwent opening and reverse faulting during the inflation period, and closure and normal faulting during and after the eruption. Stress interactions between the ring-fault and the flank dike suggest the asymmetric opening of the ring-fault promotes flank eruptions. The best-fit deformation model differs from the previous models and offers an alternative view of how magma is fed into radial dikes during flank eruptions.

Automated summary

Using InSAR data, we document surface displacements of Wolf volcano in the Galapagos Islands. We find that the volcano experienced 6 years of continuous inflation after the 2015 eruption, followed by a shallow flank eruption in January 2022. Our deformation model suggests that stress interactions between a vertical caldera ring-fault and a radial dike on the southeast flank promote flank eruptions, providing an alternative view of magma supply during these eruptions.