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Forecasting mechanical failure and the 26 June 2018 eruption of Sierra Negra Volcano, Galápagos, Ecuador

Gregg, Patricia M. and Zhan, Yan and Amelung, Falk and Geist, Dennis and Mothes, Patricia and Koric, Seid and Yunjun, Zhang (2022) Forecasting mechanical failure and the 26 June 2018 eruption of Sierra Negra Volcano, Galápagos, Ecuador. Science Advances, 8 (22). Art. No. abm4261. ISSN 2375-2548. doi:10.1126/sciadv.abm4261.

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Using recent advancements in high-performance computing data assimilation to combine satellite InSAR data with numerical models, the prolonged unrest of the Sierra Negra volcano in the Galápagos was tracked to provide a fortuitous, but successful, forecast 5 months in advance of the 26 June 2018 eruption. Subsequent numerical simulations reveal that the evolution of the stress state in the host rock surrounding the Sierra Negra magma system likely controlled eruption timing. While changes in magma reservoir pressure remained modest (<15 MPa), modeled widespread Mohr-Coulomb failure is coincident with the timing of the 26 June 2018 moment magnitude 5.4 earthquake and subsequent eruption. Coulomb stress transfer models suggest that the faulting event triggered the 2018 eruption by encouraging tensile failure along the northern portion of the caldera. These findings provide a critical framework for understanding Sierra Negra’s eruption cycles and evaluating the potential and timing of future eruptions.

Item Type:Article
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URLURL TypeDescription ItemData ItemCode
Gregg, Patricia M.0000-0003-4081-1302
Zhan, Yan0000-0002-2623-3238
Amelung, Falk0000-0003-1762-8665
Geist, Dennis0000-0003-2103-0420
Mothes, Patricia0000-0002-0650-5531
Koric, Seid0000-0002-7330-6401
Yunjun, Zhang0000-0001-9441-7082
Additional Information:© 2022 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). Submitted 16 September 2021; Accepted 15 April 2022; Published 3 June 2022. We thank two anonymous reviewers and W. Chadwick whose comments and suggestions greatly enhanced this manuscript. The development of a high-performance computing data assimilation framework for forecasting volcanic unrest is supported by grants from the U.S. National Science Foundation (OCE 1834843, EAR 1752477, and EAR 2122745 to P.M.G.), NASA (13-ESI13-0034 to F.A. and P.M.G.; 80-NSSC19K-0357 to P.M.G.), a NASA Earth and Space Science Fellowship (to Y.Z.), and a National Center for Supercomputing Applications Faculty Fellow (to P.M.G.). D.G.’s work is based on work supported while serving at the U.S. National Science Foundation. This research is part of the Blue Waters sustained petascale computing project, which is supported by the National Science Foundation (OCI-0725070 and ACI-1238993) and the state of Illinois. Blue Waters is a joint effort of the University of Illinois at Urbana-Champaign and its National Center for Supercomputing Applications. Author contributions: P.M.G. developed the EnKF approach for volcano forecasting, which Y.Z. enhanced by developing the HPC EnKF. P.M.G. and Y.Z. planned and applied the numerical implementation for Sierra Negra with high-performance computing guidance from S.K. P.M.G. developed and ran the Coulomb 3.4 models and drafted the manuscript and figures. InSAR data were processed and provided by F.A. and Z.Y. D.G. and P.M. provided background on the eruptions and the structure of the volcano. All authors discussed the results and commented on the manuscript. The authors declare that they have no competing interests. Data and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. An archive of the MintPy code can be accessed at and
Group:Seismological Laboratory
Funding AgencyGrant Number
NASA Earth and Space Science FellowshipUNSPECIFIED
National Center for Supercomputing Applications (NCSA)UNSPECIFIED
State of IllinoisUNSPECIFIED
Issue or Number:22
Record Number:CaltechAUTHORS:20220608-715906100
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Official Citation:Forecasting mechanical failure and the 26 June 2018 eruption of Sierra Negra Volcano, Galápagos, Ecuador. Patricia M. Gregg, Yan Zhan, Falk Amelung, Dennis Geist, Patricia Mothes, Seid Koric, Zhang Yunjun. Sci. Adv., 8 (22), eabm4261; DOI: 10.1126/sciadv.abm4261
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:115069
Deposited By: Tony Diaz
Deposited On:08 Jun 2022 15:42
Last Modified:08 Jun 2022 15:42

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