Deformation and seismicity decline before the 2021 Fagradalsfjall eruption

Freysteinn Sigmundsson (), Michelle Parks, Andrew Hooper, Halldór Geirsson, Kristín S. Vogfjörd, Vincent Drouin, Benedikt G. Ófeigsson, Sigrún Hreinsdóttir, Sigurlaug Hjaltadóttir, Kristín Jónsdóttir, Páll Einarsson, Sara Barsotti, Josef Horálek and Thorbjörg Ágústsdóttir
Additional contact information
Freysteinn Sigmundsson: University of Iceland
Michelle Parks: Icelandic Meteorological Office
Andrew Hooper: University of Leeds
Halldór Geirsson: University of Iceland
Kristín S. Vogfjörd: Icelandic Meteorological Office
Vincent Drouin: Icelandic Meteorological Office
Benedikt G. Ófeigsson: Icelandic Meteorological Office
Sigrún Hreinsdóttir: GNS Science
Sigurlaug Hjaltadóttir: Icelandic Meteorological Office
Kristín Jónsdóttir: Icelandic Meteorological Office
Páll Einarsson: University of Iceland
Sara Barsotti: Icelandic Meteorological Office
Josef Horálek: Institute of Geophysics, Czech Academy of Sciences, Prague 4
Thorbjörg Ágústsdóttir: Iceland GeoSurvey, ÍSOR, Urðarhvarf 8

Nature, 2022, vol. 609, issue 7927, 523-528

Abstract: Abstract Increased rates of deformation and seismicity are well-established precursors to volcanic eruptions, and their interpretation forms the basis for eruption warnings worldwide. Rates of ground displacement and the number of earthquakes escalate before many eruptions1–3, as magma forces its way towards the surface. However, the pre-eruptive patterns of deformation and seismicity vary widely. Here we show how an eruption beginning on 19 March 2021 at Fagradalsfjall, Iceland, was preceded by a period of tectonic stress release ending with a decline in deformation and seismicity over several days preceding the eruption onset. High rates of deformation and seismicity occurred from 24 February to mid-March in relation to gradual emplacement of an approximately 9-km-long magma-filled dyke, between the surface and 8 km depth (volume approximately 34 × 106 m3), as well as the triggering of strike-slip earthquakes up to magnitude MW 5.64. As stored tectonic stress was systematically released, there was less lateral migration of magma and a reduction in both the deformation rates and seismicity. Weaker crust near the surface may also have contributed to reduced seismicity, as the depth of active magma emplacement progressively shallowed. This demonstrates that the interaction between volcanoes and tectonic stress as well as crustal layering need to be fully considered when forecasting eruptions.

Date: 2022
References: Add references at CitEc
Citations: View citations in EconPapers (2)

Downloads: (external link)
https://www.nature.com/articles/s41586-022-05083-4 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:609:y:2022:i:7927:d:10.1038_s41586-022-05083-4

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-022-05083-4

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().