Computing Scheme of Co-seismic Change of Deflection of the Vertical and Applied in the 2010 Chile Earthquake
This paper introduces a scheme to compute co-seismic change of deflection of the vertical. To compare the theoretical deflection changes with the GRACE-observed ones, the dislocation Love numbers are truncated and the Green’s functions are computed with application of a Gaussian filter. This study further examines the problem of seawater correction to modeled geoid and deflection changes. As an application of the dislocation theory and the computing scheme, we consider the 2010 Chile earthquake (Mw8.8) using two fault slip models, to compute the co-seismic geoid and deflection changes considering seawater corrections. Results indicate that the co-seismic geoid and deflection changes can be detected clearly by GRACE observation, and the co-seismic geoid change is not sensitive to the fault slip models; whereas the co-seismic deflection changes are sensitive. These behaviors provide us a new and useful approach to invert seismic faults using GRACE-observed deflection changes as constraints.
Keywords2010 Chile earthquake Co-seismic deformation Deflection of the vertical Geoid
The authors thank Dr. Vigny for providing the digital fault model, and are grateful to the constructive comments by three reviewers. This study was financially supported by the CAS/CAFEA International Partnership Program for Creative Research Teams (No. KZZD-EW-TZ-19) and National Nature Science Foundation of China (Grant No. 41174063).
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