Abnormally Large Magma Flux Does Not Lead to Eruption in Subduction Zone Calderas: The 2022–2023 Episode of Uplift of Aniakchak Crater (Aleutians)

Abstract Observations of ground deformation provide insights on the triggering mechanisms of eruptions. At Aniakchak Crater (Aleutians) InSAR measured 72 cm of uplift in less than 7 months between 2022 and 2023. The uplift can be explained by the inflation of a point pressure source at a depth of 3.2 km. The infill of weak material in the caldera plays a minor role in amplifying the ground deformation signal, so magma injection is the most likely mechanism responsible for the uplift, with a time‐averaged magma flux of 1.7 /s. A global compilation of magma injection rates in subduction zones derived from satellite geodetic data indicates that rates such as those of Aniakchak are not sustained over periods of time longer than 1 year. Therefore, pulses like that on their own are usually not likely to reach the conditions that promote eruptions, unless the reservoir is very close to failure.