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

Kód výsledku v 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>

Nalezeny alternativní kódy

RIV/00216208:11310/25:10505805

Výsledek na webu

<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>

Jazyk výsledku

angličtina

Název v původním jazyce

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

Popis výsledku v původním jazyce

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.

Název v anglickém jazyce

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

Popis výsledku anglicky

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.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10507 - Volcanology

Projekt

<a href="/cs/project/GX25-16408X" target="_blank" >GX25-16408X: Komplexní geofyzikální analýza probíhající sopečné erupce na poloostrově Reykjanes</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Communications Earth & Environment

ISSN

2662-4435

e-ISSN

2662-4435

Svazek periodika

6

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

11

Strana od-do

575

Kód UT WoS článku

001535204300001

EID výsledku v databázi Scopus

2-s2.0-105011272399