Stress variations and non-shear earthquakes before the 2021 Iceland eruption trace magmatic fluid flow

Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F25%3A00637887" target="_blank" >RIV/67985530:_____/25:00637887 - isvavai.cz</a>
Alternative codes found
RIV/00216208:11310/25:10505805
Result on the web
<a href="https://www.nature.com/articles/s43247-025-02533-5" target="_blank" >https://www.nature.com/articles/s43247-025-02533-5</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1038/s43247-025-02533-5" target="_blank" >10.1038/s43247-025-02533-5</a>

Result language
angličtina
Original language name
Stress variations and non-shear earthquakes before the 2021 Iceland eruption trace magmatic fluid flow
Original language description
The 2021 Fagradalsfjall eruption on Iceland's Reykjanes Peninsula was preceded by an intense seismic swarm, offering an opportunity to investigate fluid dynamics and faulting processes at divergent plate boundary. Here we analysed 1306 full moment tensors of pre-eruption dike-related earthquakes and identified three faulting regimes: strike-slip, normal and reverse, driven by variations in vertical stress and controlled by fluid dynamics and crustal heterogeneity. Systematic volumetric components of these earthquakes revealed both tensile opening and compressive closing of cracks. Notably, crack closing dominated shallow, fractured crust, associated with surface subsidence above the dike, while crack opening occurred within the impermeable crust, suggesting overpressured fluids trapped at structural barriers. These variations highlight the role of fluid-rock interactions and anisotropic permeability in driving fault behaviour. Our results demonstrate that non-double-couple components of earthquakes are sensitive indicators of evolving stress and fluid migration. They provide insights into the mechanics of seismo-volcanic unrest at the slow-spreading rift.
Czech name
—
Czech description
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Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10507 - Volcanology

Project
<a href="/en/project/GX25-16408X" target="_blank" >GX25-16408X: Comprehensive geophysical analysis of the ongoing volcanic eruption at the Reykjanes peninsula</a><br>
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

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