Unrest at the Laguna del Maule volcanic field 2005–2020: renewed acceleration of deformation
Hélène Le Mével, Loreto Córdova, Carlos Cardona, K. L. Feigl
Abstract
Abstract The Laguna del Maule volcanic field in Chile has been exhibiting unrest since 2005. New GPS and InSAR data reveal a second episode of accelerated deformation beginning in late 2016 and continuing through May 2020, with an uplift rate > 290 mm/year between 2019 and 2020. To explain the spatial and temporal pattern of deformation, we apply a dynamic model of viscous magma flowing through a conduit into a fluid-filled reservoir surrounded by a heterogeneous, viscoelastic crust. A Monte Carlo procedure optimizes the ellipsoid reservoir geometry and the inlet pressure history. The two episodes of accelerating uplift are each modeled with a pressure increase rate of $\sim $ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>∼</mml:mo> </mml:math> 9 MPa/year. Since 2016, 0.10 km 3 of magma was injected into the system for a total of 0.37 km 3 since 2005.