From earthquake swarm to a mainshock-aftershocks: the 2018 activity in West Bohemia/Vogtland

0536049 - GFÚ 2022 RIV GB eng J - Článek v odborném periodiku
Bachura, Martin - Fischer, T. - Doubravová, Jana - Horálek, Josef
From earthquake swarm to a mainshock-aftershocks: the 2018 activity in West Bohemia/Vogtland.
Geophysical Journal International. Roč. 224, č. 3 (2021), s. 1835-1848. ISSN 0956-540X. E-ISSN 1365-246X
Grant CEP: GA ČR(CZ) GA18-05053S
Institucionální podpora: RVO:67985530
Klíčová slova: seismicity and tectonics * earthquake source observations * statistical seismology
Obor OECD: Volcanology
Impakt faktor: 3.352, rok: 2021
Způsob publikování: Omezený přístup
https://academic.oup.com/gji/article/224/3/1835/5955445

In earthquake swarms, seismic energy is released gradually by many earthquakes without a dominant event, which offers detailed insight into the processes on activated faults. The swarm of May 2018 that occurred in West Bohemia/Vogtland region included more than 4000 earthquakes with ML =(0.5, 3.8&x3009 x232A, and its character showed significant changes during the two weeks duration: what started as a pure earthquake swarm ended as a typical main shock-aftershock sequence. Based on precise double-difference relocations, four fault segments differing in strikes and dips were identified with similar dimensions. First, two segments of typical earthquake swarm character took place, and at the end a fault segment hosting a main shock-aftershock sequence was activated. The differences were observable in the earthquakes spatio-temporal evolutions (systematic versus disordered migration of the hypocentres), b-values (>1.3 for the swarm, <1 for the main shock-aftershocks), or the smoothness of seismic moment spatial distribution along the fault plane. Our findings can be interpreted by local variations of fault rheology, differential stress and/or smoothness of the faults surface, possibly related to the crustal fluids circulating along the fault plane and their interplay with the seismic cycle.
Trvalý link: http://hdl.handle.net/11104/0313893