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DOI	10.1016/j.tecto.2020.228709
	Source mechanism and triggered large aftershocks of the Mw 6.5 Ambon, Indonesia earthquake
	Sahara D.P.; Nugraha A.D.; Muhari A.; Rusdin A.A.; Rosalia S.; Priyono A.; Zulfakriza Z.; Widiyantoro S.; Puspito N.T.; Rietbrock A.; Lesmana A.; Kusumawati D.; Ardianto A.; Baskara A.W.; Halauwet Y.; Shiddiqi H.A.; Rafie M.T.; Pradisti R.; Mozef P.W.; Tuakia M.Z.; Elly E.
发表日期	2021
ISSN	00401951
卷号	799
英文摘要	On September 26, 2019, a significant, Mw 6.5, earthquake shook Ambon region, Indonesia, causing severe damage on the Island(s) of Ambon. Due to the complexity of the fault network and in-situ stress field it was, up to now, not possible to define the fault plane using data from the BMKG regional seismic network. In this study, we analyze the fault plane of the 2019 Ambon earthquake and the reactivation potential of the surrounding faults using local networks. Eleven stations were deployed to monitor the aftershocks from October 18th to December 15th, 2019 augmented with data of four regional stations. During the monitoring period, 1,778 events were identified comprised of 10,938 P- and 10,315 and S- wave arrival times. The locations of aftershock were determined in a stepwise approach, i.e. (i) initial location determination using a non-linear approach, (ii) updating the velocity model, and (iii) relative double-difference relocation. Slip inversion using teleseismic data was performed to infer of high strain relief of the mainshock and to compute its associated static stress transfer (ΔCFF). Based on aftershock distribution and finite fault modeling, we conclude that the Mw 6.5 Ambon earthquake occurred on a N-S oriented fault plane. Two clusters consisting of ~60% of total events are located at both tips of the plane. Another cluster ~30% was sharply aligned in a NE-SW trend, 10 km westward, starting by an Mw 5.2 event on November 2nd, 2019. The b-value of the NE-SW events is ~0.25 lower than the other clusters with a b-value of 0.85±0.14. ΔCFF imparted by the mainshock caused ~0.5 Bar stress increase on the NE-SW fault. We concluded that the NE-SW trend was the reactivation of a preexisting fault crossing Ambon Island. The triggered large aftershock caused further significant damages to already weakened infrastructure and, thus, had the largest mapped damage area. © 2020 Elsevier B.V.
关键词	2019 Ambon earthquake Fault network Local seismic network Source mechanism Stress transfer
英文关键词	Earthquake effects; Relocation; Shear waves; Stress relief; Stresses; Aftershock distributions; Double differences; Finite fault modeling; In-situ stress field; Location determination; Monitoring periods; Nonlinear approach; Stepwise approach; Faulting; aftershock; earthquake event; earthquake trigger; fault plane; fault zone; P-wave; S-wave; seismic source; stress field; Ambon [Moluccas]; Maluku [Indonesia]; Moluccas; Varanidae
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/208063
作者单位	Global Geophysics Research Group, Institut Teknologi Bandung, Bandung, Indonesia; Center for Earthquake Science and Technology (CEST), Research Center for Disaster Mitigation, Institut Teknologi Bandung, Bandung, Indonesia; National Disaster Management Authority of Indonesia, Jakarta, Indonesia; Agency for Meteorology, Climatology and Geophysics of Indonesia, Ambon, Indonesia; Faculty of Engineering, Maranatha Christian University, Bandung, Indonesia; Geophysical Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany; Geophysical Engineering Study Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, Indonesia; Department of Earth Science, University of Bergen, Allègaten 41, Bergen, N-5007, Norway; Geological Engineering Study Program, Pattimura University, Ambon, Indonesia
推荐引用方式 GB/T 7714	Sahara D.P.,Nugraha A.D.,Muhari A.,et al. Source mechanism and triggered large aftershocks of the Mw 6.5 Ambon, Indonesia earthquake[J],2021,799.
APA	Sahara D.P..,Nugraha A.D..,Muhari A..,Rusdin A.A..,Rosalia S..,...&Elly E..(2021).Source mechanism and triggered large aftershocks of the Mw 6.5 Ambon, Indonesia earthquake.Tectonophysics,799.
MLA	Sahara D.P.,et al."Source mechanism and triggered large aftershocks of the Mw 6.5 Ambon, Indonesia earthquake".Tectonophysics 799(2021).