Rhyolite magma has fuelled some of the Earth’s largest explosive volcanic eruptions1. Our understanding of these events is incomplete, however, owing to the previous lack of directly observed eruptions. Chaitén volcano, in Chile’s northern Patagonia, erupted rhyolite magma unexpectedly and explosively on 1 May 2008 (ref. 2). Chaitén residents felt earthquakes about 24 hours before ash fell in their town and the eruption escalated into a Plinian column. Although such brief seismic forewarning of a major explosive basaltic eruption has been documented3, it is unprecedented for silicic magmas. As precursory volcanic unrest relates to magma migration from the storage region to the surface, the very short pre-eruptive warning at Chaitén probably reflects very rapid magma ascent through the sub-volcanic system. Here we present petrological and experimental data that indicate that the hydrous rhyolite magma at Chaitén ascended very rapidly, with velocities of the order of one metre per second. Such rapid ascent implies a transit time from storage depths greater than five kilometres to the near surface in about four hours. This result has implications for hazard mitigation because the rapidity of ascending rhyolite means that future eruptions may provide little warning.
This is a preview of subscription content, access via your institution
Open Access articles citing this article.
Nature Communications Open Access 11 August 2022
Scientific Reports Open Access 05 April 2022
Bulletin of Volcanology Open Access 06 December 2021
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Get time limited or full article access on ReadCube.
All prices are NET prices.
Wilson, C. J. N. & Walker, G. P. L. The Taupo eruption, New Zealand. I. General aspects. Phil. Trans. R. Soc. Lond. A 314, 199–228 (1985)
Carn, S. et al. The unexpected awakening of Chaitén volcano, Chile. Eos 90, 205–206 (2009)
Soosalu, H. & Einarsson, P. Earthquake activity related to the 1991 eruption of the Hekla volcano, Iceland. Bull. Volcanol. 63, 536–544 (2002)
Kilburn, C. R. J. & Voight, B. Slow rock fracture as eruption precursor at Soufriere Hills volcano, Montserrat. Geophys. Res. Lett. 25, 3665–3668 (1998)
Roman, D. C. & Cashman, K. V. The origin of volcano-tectonic earthquake swarms. Geology 34, 457–460 (2006)
Chouet, B. Long-period volcano seismicity: its source and use in eruption forecasting. Nature 380, 309–316 (1996)
Voight, B. R. & Cornelius, R. R. Prospects for eruption prediction in near real-time. Nature 350, 695–698 (1991)
Tuffen, H., Smith, R. & Sammonds, P. Evidence for seismogenic fracture of silicic magma. Nature 253, 511–514 (2008)
Lavallée, Y. et al. Seismogenic lavas and explosive eruption forecasting. Nature 453, 507–510 (2008)
Gardner, J. E., Hilton, M. & Carroll, M. R. Experimental constraints on degassing of magma: isothermal bubble growth during continuous decompression from high pressure. Earth Planet. Sci. Lett. 168, 201–218 (1999)
Llewellin, E. W. & Manga, M. Bubble suspension rheology and implications for conduit flow. J. Volcanol. Geotherm. Res. 143, 205–217 (2005)
Kilburn, C. R. J. & Sammonds, P. R. Maximum warning times for imminent volcanic eruptions. Geophys. Res. Lett. 32, L24313 (2005)
Rutherford, M. J. in Minerals Inclusions and Volcanic Processes (eds Putirka, K. D. & Tepley, F. J.) 241–271 (Mineralogical Society of America, 2008)
Watt, S. et al. Fallout and distribution of volcanic ash over Argentina following the May 2008 explosive eruption of Chaitén, Chile. J. Geophys. Res. 114 B04207 10.1029/2008JB006219 (2009)
Blundy, J., Cashman, K. & Humphreys, M. Magma heating by decompression-driven crystallization beneath andesite volcanoes. Nature 443, 76–80 (2006)
Naranjo, J. A. & Stern, C. R. Holocene tephrochronology of the southernmost part (42°30'-45°S) of the Andean Southern Volcanic Zone. Rev. Geol. Chile 31, 291–306 (2004)
Hammer, J. E. & Rutherford, M. J. Petrologic indicators of pre-eruption magma dynamics. Geology 31, 79–82 (2003)
Coombs, M. L. & Gardner, J. E. Shallow-storage conditions for the rhyolite of the 1912 eruption at Novarupta, Alaska. Geology 29, 775–778 (2001)
Hammer, J. E., Rutherford, M. J. & Hildreth, W. Magma storage prior to the 1912 eruption at Novarupta, Alaska. Contrib. Mineral. Petrol. 144, 144–162 (2002)
Hammer, J. E. & Rutherford, M. J. An experimental study of the kinetics of decompression-induced crystallization in silicic melt. J. Geophys. Res. 107 10.1029//2001JB000281 (2002)
Ghiorso, M. S. & Evans, B. W. Thermodynamics of rhombohedral oxide solid solutions and a revision of the Fe-Ti two-oxide geothermometer and oxygen-barometer. Am. J. Sci. 308, 957–1039 (2008)
Castro, J. M. & Gardner, J. E. Did magma ascent rate control the explosive-effusive transition at the Inyo volcanic chain, CA? Geology 36, 279–282 (2008)
Papale, P. Strain-induced magma fragmentation in explosive eruptions. Nature 397, 425–428 (1999)
Dingwell, D. B. Volcanic dilemma: flow or blow? Science 273, 1054–1055 (1996)
Giordano, D., Russell, J. K. & Dingwell, D. B. Viscosity of magmatic liquids: A model. Earth Planet. Sci. Lett. 271, 123–134 (2008)
Gonnermann, H. M. & Manga, M. Explosive volcanism may not be an inevitable consequence of magma fragmentation. Nature 426, 432–435 (2003)
Tuffen, H., Dingwell, D. B. & Pinkerton, H. Repeated fracture and healing of silicic magma generate flow banding and earthquakes? Geology 31, 1089–1092 (2003)
Smith, R., Kilburn, C. R. J. & Sammonds, P. R. Rock fracture as a precursor to lava dome eruptions at Mount St. Helens from June 1980 to October 1986. Bull. Volcanol. 69, 681–693 (2007)
Scandone, R., Cashman, K. V. & Malone, S. D. Magma supply, magma ascent and the style of volcanic eruptions. Earth Planet. Sci. Lett. 253, 513–529 (2007)
Castro, J. M. et al. Timescales of spherulite crystallization inferred from water concentration profiles. Am. Mineral. 93, 1816–1822 (2008)
Bacon, C. R. & Hirschmann, M. M. Mg/Mn partitioning as a test for equilibrium between coexisting Fe-Ti oxides. Am. Mineral. 73, 57–61 (1988)
Silver, L. A., Ihinger, P. D. & Stolper, E. The influence of bulk composition on the speciation of water in silicate glasses. Contrib. Mineral. Petrol. 104, 142–162 (1989)
We are grateful for funding from the Alexander von Humboldt Stiftung, the Smithsonian Institution, and ERC grant 202844. N. La Penna provided an eyewitness account of the eruption sequence and critical field assistance. We thank T. Fehr, S. Bernstein and A. Logan for their analytical support. M. Rutherford and H. Tuffen provided comments that greatly improved the manuscript.
Author Contributions J.M.C. collected samples, performed the experiments and analytical work, and co-wrote the paper. D.B.D. analysed data and co-wrote the paper.
This file contains Supplementary Figures 1 and 2 with Legends and Legends for Supplementary Tables 1-4. (PDF 1282 kb)
This table indicates the experimental conditions (T,P, duration), and results of phase equilibrium and decompression experiments conducted on the Chaitén pumice (see file s1). (XLS 41 kb)
This table provides the compositions of experimentally produced plagioclase and orthopyroxene microlites (see file s1). (XLS 19 kb)
This table provides the spectral information and water concentrations in Chaitén obsidians and plagioclase-hosted glass inclusions as determined by FTIR (see file s1). (XLS 36 kb)
This table provides the compositions of coexisting titanomagnetite and ilmenite grains in the Chaitén pumice (see file s1). (XLS 19 kb)
About this article
Cite this article
Castro, J., Dingwell, D. Rapid ascent of rhyolitic magma at Chaitén volcano, Chile. Nature 461, 780–783 (2009). https://doi.org/10.1038/nature08458
This article is cited by
Scientific Reports (2022)
Nature Communications (2022)
Contributions to Mineralogy and Petrology (2022)
Nucleation delay in water-saturated rhyolite during decompression in shallow volcanic systems and its implications for ascent dynamics
Bulletin of Volcanology (2022)
Bulletin of Volcanology (2022)