Splay-fault rupture during the 2014 Mw7.1 Molucca Sea, Indonesia, earthquake determined from GPS measurements

The coseismic slip of the 2014 Molucca Sea, Indonesia, earthquake (MOSEQ) is investigated using GPS data from continuously monitoring stations. Coseismic fault models are compared between the main fault, with a 25° west-dipping plane, and the 65° west-dipping splay-fault plane. In analyzing this earthquake with fine faults sized resolution and homogenous fault models, we find that a splay fault ruptured during the mainshock. Our finding suggests that the 2014 MOSEQ occurred on an unmapped fault. Although we have limited GPS data available in the region, our results for coseismic slip are sufficient to explain the available GPS data. Our estimation suggesting that a maximum coseismic slip of around 36 cm occurred near the hypocenter, with cumulative seismic moment of 4.70 × 1019 N·m (Mw 7.1).