Analysis of source process and static surface deformation of the November 15, 2014 Halmahera earthquake

摘要

The November 15 2014 Halmahera earthquake (=7.3) was quite unique earthquake. This event generated tsunami waves with small amplitudes reported by BMKG. The tsunami run up heights was reported at Jailolo, Tobelo, and Manado 0.09 m, 0.01 m, and 0.03 m, respectively. A research has been conducted to understand this phenomenon using inversion method to the teleseismic body wave data from the IRIS-DMC seismic network. The Green functions were calculated using Kikuchi and Kanamori method. The result shows that there are two asperities. The maximum slip amount is 1.057 m in the second asperity (asperity B) near epicenter. The source parameters are obtained i.e. the total seismic moment= 0.4526x Nm (=7.0), and the source duration time is 25 seconds. Furthermore, to understand the impact of this earthquake, we have also investigated the static surface deformation around the earthquake event particularly in the land area by using forward modeling to the slip distribution data. The results show that the predicted static surface deformation at Manado is 0.0021 m, Tobelo 0.0045 m, and the largest amount is 0.0073 m at Ibu, respectively.