ABSTRACT
The 7.8 Kaikōura earthquake on 13 November 2016 is one of the most complex events ever recorded, with surface rupture found on more than a dozen faults. Within about 10 minutes after the mainshock, an 5.8 event occurred and caused an 8 cm static displacement at high‐rate Global Positioning System (GPS) station KAIK, which was not accounted for in previous mainshock studies. In this article, we focus on the 5.8 aftershock including (1) relocating the hypocenter using the hypo2000 method, (2) conducting a grid search for its point‐source mechanism and centroid location using seismic waveforms at four nearby stations, (3) inverting finite‐fault models of this event based on grid‐searched fault mechanism, and (4) calculating the surface ground deformation and estimating the deformation in the line of sight (LoS) directions of the ascending and descending Advanced Land Observation Satellite‐2 (ALOS‐2). Although we are not able to resolve the ruptured fault of the 5.8 aftershock because of limited observation data, we estimate that this event can generate 10–20 cm ground surface displacement and affect the ground displacement observed on the Interferometric Synthetic Aperture Radar (InSAR) data near the Kaikōura Peninsular.