B. Kamaruddin¹ , I. Suardi²

¹Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG), Geophysical Station of Ternate, Ternate, Indonesia
²Indonesian State College for Meteorology Climatology and Geophysics (STMKG), Banten, Indonesia

Abstract:

Iterative Joint Inversion is one of the methods which is used to determine stress orientation based on earthquake focal mechanism data. The determination of stress orientation from earthquakes is very useful for disaster mitigation. This research used the Iterative Joint Inversion method to determine stress orientation in the double subduction zone of the Maluku Sea region. The earthquake focal mechanism data were retrieved from The Global CMT (Centroid Moment Tensor) catalogue with a range of time from January 1, 2011 until December 31, 2015, and within a magnitude range of from Mw 4 to Mw 7. The results of this research are values of Friction, Shape Ratio and azimuth/plunge of each axis, respectively. The values of Friction are 0.6 and Shape Ratio is 0.67, while the values of azimuth/plunge are as follows: the T-axis is 302.24°/6.52°, the B-axis is 32.81°/4.94°, and the P-axis is 159.68°/81.80°. Based on these results it can be concluded that the stress orientation in the double subduction zone of the Maluku Sea Region is categorized as a Normal Fault.