Long Unrest (2007–2025) at Laguna del Maule: Linking Strain Field and Seismicity From GNSS and Seismic Data

Abstract The Laguna del Maule volcanic field in Chile has been uplifting at exceptional rates since 2007, offering a unique opportunity to examine the interplay between crustal deformation and magma dynamics. To understand this relationship, we integrate GNSS with local seismic observations from 2013 to 2024 to model the reservoir strain field, relocate earthquakes, and determine focal mechanisms. Our preferred model identifies a shallow spheroidal reservoir at ∼4 km depth that underwent ∼15 MPa of overpressure and a volume change increase of ∼0.23 km 3 . Seismicity clusters align with dilatational strain, and focal mechanisms are dominated by strike‐slip faulting consistent with the regional NE–SW tectonic stress regime. We distinguish two phases of unrest: 2013–2018, when seismicity concentrated in dilatational faults, and 2018–2024, when swarms became more energetic with increased magma flux and strain rates. These results demonstrate how magma input, crustal deformation, and faulting interact during prolonged volcanic unrest.