Details

Autor(en) / Beteiligte

• Mesimeri, Maria
• Karakostas, Vassilios
• Papadimitriou, Eleftheria
• Tsaklidis, George

Titel

Characteristics of earthquake clusters: Application to western Corinth Gulf (Greece)

Ist Teil von

• Tectonophysics, 2019-09, Vol.767, p.228160, Article 228160

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2019

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The western Corinth Gulf, one of the most seismically active areas in Greece with frequent earthquake sequences and a dense seismological network, is an ideal region for investigating the properties of earthquake clusters. We study 47 earthquake clusters identified using a high-resolution earthquake catalog and the CURATE clustering algorithm. Based on the skewness and kurtosis of their moment release history, 31 sequences are successfully distinguished as earthquake swarms and 13 as mainshock-aftershock sequences (three sequences could not be classified). The relationship between skewness and kurtosis leads to a parabola where mainshock–aftershock sequences are located to the right part (high values of skewness and kurtosis), whereas earthquake swarms to the center–left (low values of skewness and kurtosis). This discrimination is validated by taking into consideration the occurrence time of the largest event in the sequence, as well as the difference in magnitude between the largest event and other larger events. Twelve clusters, which consist of several burst-like repeaters, show evidence of fluid driven activity with diffusivity ranging from 0.5 to 1.8 m2/s for the triggering front and 0.1 to 0.4 m2/s for the back front. The observed temporal evolution of earthquake swarms compared to that expected from the ETAS stochastic model shows that they have distinct values for the model parameters α and μ. Finally, interevent time distributions for four clusters having at least 100 events show that a Lognormal distribution fits best in all cases, suggesting a degree of triggering between subsequent events. •Parabolic relationship between skewness and kurtosis for MS-AS and earthquake swarms•Fluid driven earthquake swarms in western Corinth Gulf•Interevent time distribution described by Lognormal