Abstract
Changes in plate coupling off the coast of Fukushima have been detected by GPS since 2000. These changes occurred close to the rupture initiation area of the Mw9.0 2011 Tohoku earthquake and possibly initiated the earthquake. We investigated these changes with quasi-dynamic earthquake cycle simulations using a hierarchical asperity model. We modeled the entire rupture region as rate weakening but conditionally stable, while areas with huge slips and Mw7 asperities were modeled as strong and ordinary rate-weakening unstable friction, respectively. The following observed characteristics were reproduced: long recurrence time, large rupture region (including a localized huge coseismic slip area and source area of recurring Mw7 earthquakes), and a Mw7 foreshock triggering the Tohoku earthquake. Off Fukushima, repeated aseismic slips propagating northward appeared in the last half of the cycle and possibly caused the decrease in plate coupling. However, it is not necessarily related to the immediate occurrence of the giant earthquake.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.