The 2020-2021 seismic sequence in the Western Gulf of Corinth: Insights on the triggering mechanisms through high resolution seismological and geodetic data analysis

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F23%3A10473399" target="_blank" >RIV/00216208:11320/23:10473399 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Vb6GfsN3mG" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Vb6GfsN3mG</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.tecto.2023.230011" target="_blank" >10.1016/j.tecto.2023.230011</a>

Result language

angličtina

Original language name

The 2020-2021 seismic sequence in the Western Gulf of Corinth: Insights on the triggering mechanisms through high resolution seismological and geodetic data analysis

Original language description

The 2020-2021 seismic sequence at the Western Gulf of Corinth, Central Greece, has been thoroughly analyzed using seismological and geodetic data processing. We present a high-resolution dataset of over 4000 relocated earthquakes between June 2020 and February 2021, delineating the activated structures. We examine the evolution of various clusters that were triggered during a three-stage sequence which began on December 23, 2020, with an Mw = 4.6 event near Marathias, migrated eastwards, following an Mw = 5.0 event on January 12, 2021 near Trizonia Island, and culminated on February 17 with an Mw = 5.3 offshore event north of Psatho-pyrgos. Focal mechanisms for the 20 stronger events, determined by moment tensor inversion, and 36 weaker ones, obtained through first motion polarities measurements, revealed dominant normal faulting. The fault plane of the February 17, 2021 major event is modeled through the inversion of geodetic data. Results suggest a very shallow geodetic centroid at 1.5 km depth, consistent with the seismic centroid (3.5 km), but different from the relocated hypocenter (7.5 km). Spatiotemporal analysis reveals seismic migration, following a diffusion law with D values in the range 0.06-0.25 m2s  1, consistent with triggering due to pore-pressure diffusion by fluids intrusion. This enables failure on non-optimally oriented faults, which explains the significant proportion of the observed strike-slip and oblique-normal faulting. Coulomb stress transfer due to the major events shows only weak stress-loading on the fault of the January 12, 2021 earthquake and a higher level of positive stress transfer to the south-dipping than to the north-dipping nodal plane of the 17 February event. The latter could have facilitated the nucleation of the rupture at 7.5 km and its further propagation to shallower depths along a south-dipping plane, where the bulk of its seismic and geodetic moment was released.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10500 - Earth and related environmental sciences

Project

<a href="/en/project/GA23-06345S" target="_blank" >GA23-06345S: Seismo-geodynamic modeling of the Hellenic subduction</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2023

Confidentiality

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

Name of the periodical

Tectonophysics

ISSN

0040-1951

e-ISSN

1879-3266

Volume of the periodical

863

Issue of the periodical within the volume

August

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

22

Pages from-to

230011

UT code for WoS article

001068437200001

EID of the result in the Scopus database

2-s2.0-85169605580