Earthquake relocation in Mollucas Sea using teleseismic double difference method for tectonic setting analysis

Earthquake hypocenter relocation is need to be done to get a better earthquake location with high accuracy so tectonic setting, and seismicity analysis can be get and done for further studies. One of some method to relocate earthquake is teleseismic Double-Difference that used 3D velocity model. This research is done by relocating 7042 of 8845 available earthquakes from January 1st 2009 – June 12th 2016 in Moluccas Sea. The result are better earthquake depths, showed by no more fixed depth earthquakes and hypocenter distribution shows subduction pattern which is assossiated to Moluccas Sea Plate. Subducting Plate of Moluccas Sea below Sangihe is getting deeper more way it gets north (± 580 km) and sloping to the south (± 280 km) and the subducting Moluccas Sea below Halmahera Arc is 250 km depth on average. Another result is a rollback of Phillipine plate is found that moves along with Moluccas Sea plate which is subducting below Halmahera Arc.