2026-04-17T03:19:15Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/2265182026-04-07T23:24:46Zcom_2072_1057col_2072_478917col_2072_478923

00925njm 22002777a 4500 dc Lopez, Carmén author Benito-Saz, Maria A. author Marti Ribas, Josep author del-Fresno, Carmen author García‐Cañada, Laura author Albert Mínguez, Helena author Lamolda, Héctor author 2026-02-02T07:51:59Z 2026-02-02T07:51:59Z 2017 2026-02-02T07:51:59Z We reanalyzed the seismic and deformation data corresponding to the preeruptive unrest on El Hierro (Canary Islands) in 2011. We considered new information about the internal structure of the island. We updated the seismic catalog to estimate the full evolution of the released seismic energy and demonstrate the importance of nonlocated earthquakes. Using seismic data and GPS displacements, we characterized the shear-tensile type of the predominant fracturing and modeled the strain and stress fields for different time periods. This enabled us to identify a prolonged first phase characterized by hydraulic tensile fracturing, which we interpret as being related to the emplacement of new magma below the volcanic edifice on El Hierro. This was followed by postinjection unidirectional migration, probably controlled by the stress field and the distribution of the structural discontinuities. We identified the effects of energetic magmatic pulses occurring a few days before the eruption that induced shear seismicity on preexisting faults within the volcano and raised the Coulomb stress over the whole crust. We suggest that these magmatic pulses reflect the crossing of the Moho discontinuity, as well as changes in the path geometry of the dyke migration toward the surface. The final phase involved magma ascent through a prefractured crust. Magmatisme Vulcanisme Geodinàmica Erupcions volcàniques Magmatism Volcanism Geodynamics Volcanic eruptions Driving magma to the Surface: the 2011-2012 El Hierro volcanic eruption