Articles | Volume 14, issue 1
https://doi.org/10.5194/se-14-69-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-14-69-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
23 Jan 2023
Research article | Highlight paper |
| 23 Jan 2023
| 23 Jan 2023
Anatomy of a high-silica eruption as observed by a local seismic network: the June 2011 Puyehue–Cordón Caulle event (southern Andes, Chile)
Daniel Basualto
Departamento de Ingeniería en Obras Civiles, Facultad de
Ingeniería y Ciencias, Universidad de La Frontera (UFRO), Francisco
Salazar 01145, Temuco, Chile
Programa de Doctorado en Ciencias Geológicas, Universidad de
Concepción, Víctor Lamas 1290, Concepción, Chile
Programa de Doctorado en Ciencias Geológicas, Universidad de
Concepción, Víctor Lamas 1290, Concepción, Chile
Departamento Ciencias de la Tierra, Facultad de Ciencias
Químicas, Universidad de Concepción, Víctor Lamas 1290,
Concepción, Chile
Núcleo Milenio CYCLO: The Seismic Cycle along Subduction Zones, Concepción,
Chile
Jonathan Lazo-Gil
Departamento de Ciencias Físicas, Universidad de La Frontera,
Casilla 54-D, Temuco, Chile
Luis Franco-Marin
Servicio Nacional de Geología y Minería (SERNAGEOMIN) – Red
Nacional de Vigilancia Volcánica (RNVV) – Observatorio Volcanológico
de los Andes del Sur, (OVDAS), Rudecindo Ortega 03850, Temuco, Chile
Carlos Cardona
Servicio Nacional de Geología y Minería (SERNAGEOMIN) – Red
Nacional de Vigilancia Volcánica (RNVV) – Observatorio Volcanológico
de los Andes del Sur, (OVDAS), Rudecindo Ortega 03850, Temuco, Chile
Juan San Martín
Departamento de Ciencias Físicas, Universidad de La Frontera,
Casilla 54-D, Temuco, Chile
Fernando Gil-Cruz
Servicio Nacional de Geología y Minería (SERNAGEOMIN) – Red
Nacional de Vigilancia Volcánica (RNVV) – Observatorio Volcanológico
de los Andes del Sur, (OVDAS), Rudecindo Ortega 03850, Temuco, Chile
Marcela Calabi-Floddy
Nano-biotechnology Laboratory, Center of
Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and
Biotechnological Bioresource Nucleus, BIOREN-UFRO, Universidad de La Frontera, Francisco Salazar 01145, Temuco, Chile
Cristian Farías
Departamento de Geología y Obras Civiles, Facultad de
Ingeniería, Universidad Católica de Temuco, Rudecindo Ortega 02950,
Temuco, Chile
Related authors
Ivo Fustos-Toribio, Daniel Basualto, Ardy Gatica, Alvaro Bravo-Alarcón, José-Luis Palma, Gabriel Fuentealba, and Sergio A. Sepúlveda
EGUsphere, https://doi.org/10.5194/egusphere-2025-1394, https://doi.org/10.5194/egusphere-2025-1394, 2025
Short summary
Short summary
We investigated how volcanic soils and heavy rainfall trigger dangerous debris flows in the southern Andes. Our findings show saturated volcanic-soils above less permeable glacial deposits create ideal conditions for slope failures. Monitoring soil moisture and surface changes helps predict these events. This knowledge aids in protecting communities from debris flow hazards, increasingly important under climate change.
Ivo Fustos-Toribio, Daniel Basualto, Ardy Gatica, Alvaro Bravo-Alarcón, José-Luis Palma, Gabriel Fuentealba, and Sergio A. Sepúlveda
EGUsphere, https://doi.org/10.5194/egusphere-2025-1394, https://doi.org/10.5194/egusphere-2025-1394, 2025
Short summary
Short summary
We investigated how volcanic soils and heavy rainfall trigger dangerous debris flows in the southern Andes. Our findings show saturated volcanic-soils above less permeable glacial deposits create ideal conditions for slope failures. Monitoring soil moisture and surface changes helps predict these events. This knowledge aids in protecting communities from debris flow hazards, increasingly important under climate change.
Ayleen Gaete, Thomas R. Walter, Stefan Bredemeyer, Martin Zimmer, Christian Kujawa, Luis Franco Marin, Juan San Martin, and Claudia Bucarey Parra
Nat. Hazards Earth Syst. Sci., 20, 377–397, https://doi.org/10.5194/nhess-20-377-2020, https://doi.org/10.5194/nhess-20-377-2020, 2020
Short summary
Short summary
Phreatic eruptions often occur without signs of enhanced volcanic unrest, avoiding detection and posing a threat to people in the vicinity. We analyzed data of the 2015 phreatic eruption of Lascar volcano, Chile, to retrospectively identify a precipitation event as the trigger mechanism and potential signs heralding this minor eruption. We showed that it is possible to detect the precursory activity of phreatic eruptions by deploying appropriate multiparametric monitoring.
Carolyne Pickler, Edmundo Gurza Fausto, Hugo Beltrami, Jean-Claude Mareschal, Francisco Suárez, Arlette Chacon-Oecklers, Nicole Blin, Maria Teresa Cortés Calderón, Alvaro Montenegro, Rob Harris, and Andres Tassara
Clim. Past, 14, 559–575, https://doi.org/10.5194/cp-14-559-2018, https://doi.org/10.5194/cp-14-559-2018, 2018
Short summary
Short summary
We compiled 31 temperature–depth profiles to reconstruct the ground surface temperature of the last 500 years in northern Chile. They suggest that the region experienced a cooling from 1850 to 1980 followed by a warming of 1.9 K. The cooling could coincide with a cooling interval in 1960. The warming is greater than that of proxy reconstructions for nearby regions and model simulations. These differences could be due to differences in spatial and temporal resolution between data and models.
Cited articles
Alloway, B. V., Pearce, N. J. G., Villarosa, G., Outes, V., and Moreno, P.
I.: Multiple melt bodies fed the AD 2011 eruption of
Puyehue-CordónCaulle, Chile, Sci. Rep.-UK, 5, 17589, https://doi.org/10.1038/srep17589, 2015.
Alparone, S., Andronico, D., Lodato, L., and Sgroi, T.: Relationship between tremor and volcanic activity during the Southeast Crater eruption on Mount Etna in early 2000, J. Geophys. Res., 108, 2241, https://doi.org/10.1029/2002JB001866, 2003.
Aki, K.: Maximum likelihood estimates of b in the formula log N=a−bM
and its confidence limits, B. Earthq. Res. I. Tokyo, 43,
237–239, 1965.
Aki, K.: Deep Volcanic Tremor and Magma Ascent MechanismUnder Kilauea,
Hawaii, J. Geophys. Res., 86, 7095–7109,
1981.
Aki, K.: Evidence for magma intrusion during the Mammoth Lakes earthquakes
of May 1980 and implication of the absence of volcanic (Harmonic) Tremor,
J. Geophys. Res., 89, 7689–7696, 1984.
Bean, C., De Barros, L., Lokmer, I., Métaxian, J. P., O'Brien, G., and Murphy S.: Long-period seismicity in the shallow volcanic edifice formed from slow-rupture earthquakes, Nat. Geosci., 7, 71–75, https://doi.org/10.1038/ngeo2027, 2014.
Bertin, D., L. Lara., Basualto, D., Amigo, A., Cardona, C., Franco, F., Gil,
F., and Lazo, J.: High effusion rates of the CordónCaulle 2011-12
eruption (Southern Andes) and theirrelation with the quasi-harmonic tremor,
Geophys. Res. Lett., 42, 7054–7063, https://doi.org/10.1002/2015GL064624, 2015.
Boatwright, J.: A spectral theory for circular seismic sources: simple
estimates of source dimension, dynamic stress drop, and radiated seismic
energy, B. Seismol. Soc. Am., 70, 1–27, 1980.
Bohm M., Lüth S., Echtler H., Asch G., Bataille K., Bruhn C., Rietbrock
A., and Wigger P.: The Southern Andes between 36∘ and
40∘ S latitude: seismicity and average seismic velocities,
Tectonophysics, 356, 275–289, 2002.
Bouchon, M.: A simple method to calculate Green's functions for elastic
layered media, B. Seismol. Soc. Am., 71, 959–971, 1981.
Castro, J. M., Schipper, C. I., Mueller, S. P., Militzer, A. S., Amigo, A.,
Parejas, C. S., and Jacob, D.: Storage and eruption of near-liquidus rhyolite
magma at Cordón Caulle, Chile, B. Volcanol. 75, 702, https://doi.org/10.1007/s00445-013-0702-9, 2013.
Castro, J. M., Cordonnier, B., Schipper, C., Tuffen, I., Baumann, H.,
Tobias S., and Feisel, Y.: Rapid laccolith intrusion driven by explosive
volcanic eruption, Nat. Commun., 7, 13585,
https://doi.org/10.1038/ncomms13585, 2016.
Cembrano, J. and Lara, L.: The link between volcanism and tectonics in the
southern volcanic zone of the Chilean Andes: A review, Tectonophysics, 471,
96–113, 2009.
Chouet, B.: Volcano Seismology, Pure Appl. Geophys., 160, 739–788, 2003.
Crosson, R. S.: Crustal structure modelling of earthquake data, 1,
Simultaneous least squares estimation of hypocenter and velocity parameters,
J. Geophys. Res., 81, 3036–3046, 1976.
Delgado, F.: Rhyolitic volcano dynamics in the Southern Andes: Contributions
from 17 years of InSAR observations at Cordón Caulle from 2003 to 2020,
J. S. Am. Earth Sci., 43, 9552–9562, https://doi.org/10.1016/j.jsames.2020.102841, 2021.
Delgado, F., Pritchard, M., Basualto, D., Lazo, J., Córdoba, L., and Lara, L.:
Rapid reinFLation following the 2011–2012 rhyodacite eruption at
CordónCaulle volcano (Southern Andes) imaged by InSAR: Evidence for
magma reservoir reFIll, Geophys. Res. Lett., 43, 9552–9562, https://doi.org/10.1002/2016GL070066, 2016.
Delgado, F., Kubanek, J., Anderson, K., Lundgren, P., and Pritchard, M.:
Physicochemical models of effusive rhyolitic eruptions constrained with
InSAR and DEM data: a case study of the 2011–2012 Cordón Caulle
eruption, Earth Planet Sc.
Lett., 524, 115736,
https://doi.org/10.1016/J.EPSL.2019.115736, 2019.
Dreger D., Tkalčić1 H., and Johnston, M.: Dilational Processes
Accompanying Earthquakes in the Long Valley Caldera, Science,
288, 122–125, https://doi.org/10.1126/science.288.5463.122, 2000.
Eggert, S. and Walter, T.: Volcanic activity before and after large
tectonic earthquakes: Observations and statistical significance,
Tectonophysics, 471, 14–26,
https://doi.org/10.1016/j.tecto.2008.10.003, 2009.
Eichelberger, J., Carrigan, C., Westrich, H., and Price, R. H.:: Non-explosive silicic
volcanism, Nature, 323, 598–602, https://doi.org/10.1038/323598a0,
1986.
Ellsworth, W. L.: Three-dimensional structure of the crust and mantle beneath
the island of Hawaii, PhD thesis, Mass. Inst. of Technol., Cambridge,
1977.
Euillades, P. A., Euillades, L. D., Blanco, M. H., Velez, M. L., Grosse, P., and Sosa, G. J.: Co-eruptive subsidence and post-eruptive uplift
associated with the 2011–2012 eruption of Puyehue-Cordón Caulle, Chile,
reveale, J. Volcanol. Geoth. Res., https://doi.org/10.1016/j.jvolgeores.2017.06.023, 2017.
Giachetti, T., Hudak, M., Shea, T., Bindeman, I., and Hoxsie, E.: D/H ratios and
H2O contents record degassing and rehydration history of rhyolitic magma and
pyroclasts, Earth Planet. Sc. Lett., 530, 115909,
https://doi.org/10.1016/j.epsl.2019.115909,
2020.
Girona, T., Costa, F., and Schubert, G.: Degassing during quiescence as a
trigger of magma ascent and volcanic eruptions, Sci Rep.-UK, 5, 18212,
https://doi.org/10.1038/srep18212, 2015.
Gutenberg, B. and Richter, C. F.: Frequency of earthquakes in California, B.
Seismol. Soc. Am., 34, 185–188, 1944.
Hamilton, R. M.: Mean magnitude of an earthquake sequence, B. Seismol. Soc.
Am., 57, 1115–1116, 1967.
Hardebeck, H. and Shearer, P.: Using S/P Amplitude Ratios to Constrain the
Focal Mechanisms of Small Earthquakes, B. Seismol. Soc.
Am., 93, 2434–2444, 2003.
Havskov, J. and Ottemöller, L.: SEISAN earthquake analysis software, Seismol. Res. Lett., 70, 532–534, 1999.
Hutton, L. and Boore, D.: The ML scale in southern California, B.
Seismol. Soc. Am., 77, 2074–2094, 1987.
Jay, J., Costa, F., Pritchard, M., Lara, L., Singer, B., and Herrin, J.:
Locating magma reservoirs using InSAR and petrology before and during the
2011–2012 Cordón Caulle silicic eruption, Earth Planet. Sc.
Lett., 395, 254–266, 2014.
Julian, B. R. and Sipkin, S. A.: Earthquake processes in the Long Valley
Caldera area, California, J. Geophys. Res., 90,
11155–11169, 1985.
Kissling, E., Ellsworth, W., Eberhart-Phillips D., and Kradolfer, U.: Initial
reference models in local earthquake tomography, J. Geophys. Res.-Sol. Ea., 99, 19635–19646, 1994.
Křížová, D., Zahradník, J., and Kiratzi, A.:
Resolvability of Isotropic Component in Regional Seismic Moment Tensor
Inversion, B. Seismol. Soc. Am., 103, 2460–2473, https://doi.org/10.1785/0120120097, 2013.
Lahr, J. C., Chouet, B., Stephens, C., Power, J., and Page, R.: Earthquake
classification, location, and error analysis in a volcanic environment:
implications for the magmatic system of the 1989–1990 eruptions at Redoubt
Volcano, Alaska, J. Volcanol. Geoth. Res., 62,
137–151, 1994.
La Delfa, S., Patanè, G., Clocchiatti, R., Joron, J.-L., and Tanguy, J.-C.: Activity of Mount Etna preceding the February 1999 fissure eruption: inferred mechanism from seismological and geochemical data, J. Volcanol. Geoth. Res., 105, 121–139, https://doi.org/10.1016/S0377-0273(00)00249-3, 2001.
Lara, L. E. and Moreno, H.: Geología del Complejo Volcánico
Puyehue–Cordón Caulle, X Región de Los Lagos. Servicio Nacional de
Geología y Minería, Carta Geológica de Chile, Serie
Geología Básica, 1 mapa escala 1:50.000, 2006.
Lara, L. E., Naranjo, J. A., and Moreno, H.: Rhyodacitic fissure eruption in
Southern Andes (CordónCaulle; 40.58S) after the 1960 (Mw:9.5) Chilean
earthquake: a structural interpretation, J. Volcanol. Geoth. Res., 138, 127–138, 2004.
Lara, L. E., Lavenu, A., Cembrano, J., and Rodríguez, C.: Structural
controls of volcanism in transversal chains: resheared faults and
neotectonics in Cordón Caulle–Puyehue area (40.5∘ S), Southern
Andes, J. Volcanol. Geoth. Res., 158, 70–86, 2006a.
Lara, L. E., Moreno, H., Naranjo, J. A., Matthews, S., and Pérez de Arce, C.:
Magmatic evolution of the Puyehue–CordónCaulle Volcanic Complex
(40∘ S), Southern Andean Volcanic Zone: From shield to unusual
rhyolitic fissure volcanism, J. Volcanol. Geoth. Res.,
157, 343–366, 2006b.
Lee, W. H. K. and Valdés, C. M.: HYP071PC: A personal computer version of the
HYPO71 earthquake location program, U. S. Geological Survey Open File
Report, pp. 85–749, 1985.
Matsumura, S.: Three-dimensional expression of seismic particle motion by
the trajectory ellipsoid and its application to the seismic data observed in
the Kanto district, Japan, J. Phys. Earth, 29, 211–239, 1981.
McNutt, S. R.: Volcanic tremor, in: Encyclopedia of Earth System Science, vol. 4, edited by: Nierenberg, W. A., 417–425, Academic Press, San Diego, Calif., 1992.
Montegrossi, G., Farina, A., Fusi, L., and De Biase, A.: Mathematical model for volcanic harmonic tremors, Sci. Rep.-UK, 9, 14417, https://doi.org/10.1038/s41598-019-50675-2, 2019.
National Academies of Sciences, Engineering, and Medicine: Volcanic Eruptions
and Their Repose, Unrest, Precursors, and Timing. Washington, DC, The
National Academies Press, https://doi.org/10.17226/24650, 2017.
Novoa, C., Gerbault, M., Rémy, D., Cembrano, J., Lara, L., Ruz, J.,
Tassara, A., Baez, J. C., Hassani, R., Bonvalot, S., and Contreras, R.: The 2011
Cordon Caulle eruption triggered by slip on the Liquiñe-Ofqui fault
system, Earth Planet. Sc. Lett., 583, 117386, https://doi.org/10.1016/j.epsl.2022.117386, 2022.
Oyarzún, A., Lara, L., and Tassara, A.: Decoding the plumbing system of
Nevados de Chillán Volcanic complex, Southern Andes, J.
Volcanol. Geoth. Res., 422, 107455, https://doi.org/10.1016/j.jvolgeores.2021.107455,
2022.
Piña-Gauthier, M., Lara, L., Bataille, K., Tassara, A., and Baez, J.:
Deformación co-eruptiva y crecimiento del domo durante la erupción
2008–2009 del volcán Chaitén, Andes del Sur, Andean Geol., 40,
310–323, https://doi.org/10.5027/andgeoV40n2-a08, 2013.
Piquer, J., Rivera, O., Yáñez, G., and Oyarzún, N.: The Piuquencillo fault system: a long-lived, Andean-transverse fault system and its relationship with magmatic and hydrothermal activity, Solid Earth, 12, 253–273, https://doi.org/10.5194/se-12-253-2021, 2021.
Pistolesi, M., Cioni, R., Bonadonna, C., Elissondo, M., Baumann, V.,
Bertagnini, A. Hiari, L., Gonzales, R., Rosi, M., and Francalanci, L.:
Complex dynamics of small-moderate volcanic events: The example of the 2011
rhyolitic Cordón Caulle eruption, Chile, B. Volcanol., 77, 1–24, https://doi.org/10.1007/s00445-014-0898-3, 2015.
Pritchard, M. E., Mather, T. A., McNutt, S. R., Delgado, F. J., and Reath,
K.: Thoughts on the criteria to determine the origin of volcanic unrest as
magmatic or non-magmatic, Philos. T. Roy. Soc.
A, 377, 20180008, https://doi.org/10.1098/rsta.2018.0008, 2019.
Roman, D. C. and Cashman K. V.: Top–Down Precursory Volcanic Seismicity:
Implications for “Stealth” Magma Ascent and Long-Term Eruption Forecasting,
Front. Earth Sci., 6, 124, https://doi.org/10.3389/feart.2018.00124, 2018.
Sánchez, P., Pérez-Flores, P., Arancibia, G., Cembrano, J., and
Reich, M.: Crustal deformation effects on the chemical evolution of
geothermal systems: The intra-arc Liquiñe–Ofqui fault system, Southern
Andes, Int. Geol. Rev., 55, 1384–1400,
https://doi.org/10.1080/00206814.2013.775731, 2013.
Sarao, A., Panza, G., Privitera, E., and Cocina, O.: Non-double- couple mechanisms
in the seismicity preceding the 1991–1993 Etna volcano eruption, Geophys.
J. Int., 145, 319–335, 2001.
Scandone, R., Cashman, K., and Malone, S.: Magma supply, magma ascent and the
style of volcanic eruptions, Earth Planet. Sc. Lett.,
253, 513–529,
https://doi.org/10.1016/j.epsl.2006.11.016, 2007.
Schipper, C. I., Castro, J. M., Kennedy, B. M., Tuffen, W. H., Wadsworth, F., Paisley, R., Fitzgerald, R., Rhodes, E., Schaefer, L., Ashwell, A., Forte, B., Seropian, G., and Alloway, B.: Silicic conduits as
supersized tuffisites: Clastogenic influences on shifting eruption styles at
Cordón Caulle volcano (Chile), B. Volcanol. 83, 11, 1–22, https://doi.org/10.1007/s00445-020-01432-1, 2021.
Scholz, C. H.: On the stress dependence of the earthquake b-value, Geophys.
Res. Lett., 42, 1399–1402, https://doi.org/10.1002/2014GL062863, 2015.
Schorlemmer, D., Wiemer, S., and Wyss, M.: Variations in earthquake-size
distribution across different stress regimes, Nature, 437, 539–542, 2005.
Sepúlveda, F., Lahsen, A., Bonvalot, S., Cembrano, J., Alvarado, A., and
Letelier, P.: Morphostructural evolution of the CordónCaulle geothermal
region, Southern Volcanic Zone, Chile: insights from gravity and 40Ar/39Ar
dating, J. Volcanol. Geoth. Res., 148, 165–189, 2005.
Singer, B. S., Jicha, B. R., Harper, M. A., Naranjo, J. A., Lara, L. E.,
and Moreno-Roa, H.: Eruptive history, geochronology, and magmatic evolution of
the Puyehue–CordónCaulle volcanic complex, Chile, Geol. Soc. Am. B.,
120, 599–618, 2008.
Snoke, J. A., Munsey, J. W., Teague, A. C., and Bollinger, G. A.: A program for focal mechanism determination by combined use of polarity and SV-P amplitude ratio data,
Earthquake Notes, 55, p. 15, 1984.
Sokos, E. and Zahradnik, J.: ISOLA A Fortran code and MatLab GUI to perform
multiple-point source inversion of seismic data, Comput. Geosci., 34, 967–977, 2008.
Stock, M. J., Humphreys, M. C. S., Smith, V. C., Isaia, R., and Pyle, D. M.:
Late-stage volatile saturation as a potential trigger for explosive volcanic
eruptions, Nat. Geosci., 9, 249–254,
https://doi.org/10.1038/ngeo2639, 2016.
Tassara, A. and Echaurren, A.: Anatomy of the Andean subduction zone:
three-dimensional density model upgraded and compared against global-scale
models, Geophys. J. Int., 189, 161–168, 2012.
Templeton, D. and Dreger, D.: Non-Double-Couple Earthquakes in the Long Valley
Volcanic Region, B. Seismol. Soc. Am., 96,
69–79, 2006.
Thurber, C. H.: Earthquake locations and three-dimensional crustal structure
in the Coyote Lake area, Central California, J. Geophys. Res.,
88, 8226–8236, https://doi.org/10.1029/JB088iB10p08226, 1983.
van der Elst, N. J.: B-positive: A robust estimator of aftershock magnitude distribution in transiently incomplete catalogs, J. Geophys. Res.-Sol. Ea., 126, e2020JB021027, https://doi.org/10.1029/2020JB021027, 2021.
Wendt, A., Tassara, A., Báez, J. C., Basualto, D., Lara, L.,
and García, F.: Possible structural control on the 2011 eruption of
Puyehue-CordónCaulle Volcanic Complex (southern Chile) determined by
InSAR, GPS and seismicity, Geophys. J. Int., 208, 134–147, https://doi.org/10.1093/gji/ggw355,
2016.
White, R. and McCausland, W.: Volcano-tectonic earthquakes: A new tool for
estimating intrusive volumes and forecasting eruptions, J.
Volcanol. Geoth. Res., 309, 139–155, https://doi.org/10.1016/j.jvolgeores.2015.10.020, 2016.
Wicks Jr., C. W., de la Llera, J. C., Lara, L. E., and Lowenstern, J.: The
role of dyking and fault control in the rapid onset of eruption at
Chaitén volcano, Chile, Nature, 478, 374–377,
https://doi.org/10.1038/nature10541, 2011.
Executive editor
The paper represents a very detailed study of the geophysical precursors recorded before and during a major recent explosive eruption. Moreover, the results permit to partly validate and discuss recent models of volcano unrest and have large applications for the monitoring of hazardous volcanoes worldwide.
The paper represents a very detailed study of the geophysical precursors recorded before and...
Short summary
Infrequent eruptions of acidic magma are one of the most dangerous natural phenomena, but almost none of them have been witnessed by modern science. We present the first systematic characterization of seismicity recorded near an erupting acidic volcano (Cordón Caulle 2011). We define different phases of unrest and eruption, which combined with previous findings allows us to discuss the main processes associated with this type of violent eruption, with implications for their volcanic hazard.
Infrequent eruptions of acidic magma are one of the most dangerous natural phenomena, but almost...
