Abstract
Some strong earthquakes are associated with increasing of volcanic activity in near and also in far field. This research is to investigate the effect of the tectonic earthquakes in Nusa Tenggara Island area towards the October 25 th ,2015 eruption of Mt. Rinjani, Indonesia. Three earthquakes occurred before the eruptions; M w 5 Sumba earthquake on June 10 th 2015, M w 5.8 South of Java earthaquake July 26 th , 2016 and M w 5 South of Bali on August 6 th , 2015. In theory, dynamical stress transfer can be calculated by analyzing synthetic seismogram as a waveform simulation at the volcano and the change of dynamical stress can be calculated with the finitedifference numerical method. Our result indicates that the dynamic stress value is still below the threshold value that can trigger eruptions. Simulation of three earthquakes by varying the magnitude of each earthquake shows that dynamic stress changes will surpass the threshold at M w 7.5. As all the earthquake that used in this study have magnitude smaller then the threshold, it can be concluded that the eruption of Mount Rinjani was triggered by internal factors, and very unlikely triggered by tyhe earthquake we investigated in this study.