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This article presents earthquake catalogs of the 2019 Ambon aftershocks compiled from regional the Agency for Meteorology, Climatology, and Geophysics of Indonesia (BMKG) and local seismic networks deployed in [1] . The final earthquake catalogs are comprised of 1009 and 1764 aftershocks compiled from regional [2] and local network [1] , respectively, which span the period of October 18th to December 15th, 2019. The range of their spatial region is −3.70 o to −3.30 o on the latitude and 128.15 – 128.60 o on the longitude. Additionally, focal mechanism solutions of the main Mw 6.5 and its biggest triggered aftershock Mw 5.2 events were acquired. Such datasets could provide a basis for further seismology analysis, including seismic tomography, source mechanism analysis, and further seismic hazard analysis in the Ambon and Seram islands. This paper and its dataset are a companion for a published article in the Tectonophysics under the title “Source Mechanism and Triggered Large Aftershocks of the Mw 6.5 Ambon, Indonesia Earthquake” [1] .

The Ambon Mw 6.5 earthquake on September 26th, 2019, had contributed to give severe damages and significantly increased seismicity around Ambon Island and surrounding areas. Mainshock was followed by aftershocks with spatial distribution added to the impact of destructions in this region. We investigated aftershocks sequences to reveal the effect of mainshock toward the change in the in-situ stress field, including the possibility of the existing faults reactivation and the generation of aftershocks. We inferred centroid moment tensor (CMT) for significant aftershock events with Mw more than 4.0 using waveform data recorded from October 18th to December 15th, 2019. The aftershock focal mechanism was determined using the Bayesian full-waveform inversion code ISOLA-Obspy. This approach provides the uncertainty of the CMT model parameters. From ten CMT solution we had inferred in three seismic clusters, we found that majority of events have a strike-slip mechanism. Four events located on the south of the N-S trendings have a dextral strike-slip fault type, reflected the rupture of the mainshocks fault plane. Three events in the cluster of Ambon Island are dextral strike-slip, confirming the presence of the fault reactivation. Meanwhile, three CMT solutions in the north show the dextral strike-slip faulting and may belong to the mainshock main fault, connected with the cluster in the south.

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