Abstract
A sequence of M 7-class interplate earthquakes and transient postseismic slips following each of these earthquakes occurred along the Japan Trench before the occurrence of the giant earthquake on March 11, 2011. Continuous GPS data detected a significant postseismic deformation with displacements that were much larger than that of the coseismic offset. Moreover, the geodetic inversion results using these observations revealed that the total moment released by these transient slips was much larger than the coseismic ones. This differs from our understanding of the postseismic process that the postseismic deformation and slip are smaller than the coseismic ones. These transient processes may help us understand not only the postseismic process but also the pre-seismic signals indicating the occurrence of the giant earthquake.
Highlights
A giant earthquake with a moment magnitude of 9.0 occurred at 14:46 (JST) on March 11, 2011, along the Japan Trench (Fig. 1(a))
Its duration seems to be about 2 years, as Miura et al (2006) reported. We refer to this event as a reference of postseismic deformation produced by an afterslip in this study
A number of studies have reported that the postseismic signals produced by an afterslip rapidly decay with time and the amount of displacement is less than or equal to the coseismic offset, the decay time and duration of the signal are different for each earthquake and may depend on its mechanisms (e.g., Heki et al, 1997; Gahalaut et al, 2008; Perfettini et al, 2010)
Summary
A giant earthquake with a moment magnitude of 9.0 occurred at 14:46 (JST) on March 11, 2011, along the Japan Trench (Fig. 1(a)). The time series of the GPS data in the east-west component clearly reveals coseismic offset and subsequent transient deformation at each earthquake (Fig. 1(b)). Based on these time series, we look into the spatial distribution of each coseismic and postseismic deformation (Fig. 2).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
