Tomographic and volcanotectonic control on the 2021-2023 Fagradalsfjall eruptions, Iceland.

ABSTRACT: Shortly before the 2021 Fagradalsfjall eruption tomographic images indicated a large high V_p/V_s anomaly with a top at about 9 km depth directly below the ongoing seismic swarm. Using volcanotectonic principles we interpret this anomaly as part of the roof of a magma reservoir which, furthermore, ruptured on 24 February 2021. The roof rupture resulted in an injected dike-segment propagating vertically at an average rate of about 0.2 m s^- 1 until it became arrested beneath a stress barrier at ~ 2 km depth, from where the dike-segment propagated laterally. Further magma injections took place, following largely the path of the first dike-segment, resulting in part of the dike reaching outside the stress barrier and propagating vertically as a tiny 'finger' to f

SUBMITTER: Hobe A 

PROVIDER: S-EPMC12069532 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature