Active tectonic regime of Java Island, Indonesia from seismic strain rate analysis

Gayatri I. Marliyani, Subagyo Pramumijoyo, & Hurien Helmi

Published August 15, 2021, SCEC Contribution #11450, 2021 SCEC Annual Meeting Poster #216

Identifying high strain-rate regions is important to characterize areas of high tectonic activity. The highly populated island of Java is part of the volcanic arc of the Sunda subduction zone in Indonesia. The area is seismically active, as indicated by numerous damaging earthquakes in recent years attributed to shallow active faulting. However, faults in this area mostly buried by thick sediments or soil and their characterization is challenging. Knowledge of the regional stress field and deformation pattern in this region will help us to anticipate seismic hazard associated with the deformation. In this study, we calculate the seismic strain rate from earthquake moment tensor data to characterize the strain field of Java’s volcanic arc. We also combine our observation with preexisting crustal deformation studies using GPS in Java, as well as stress orientation data from volcano morphology. The results enables us to identify high strain-rate region that may correlate to active faulting. Our study provides general framework to interpret large-scale structures and mechanical behavior of faulting in the overriding plate of the Java subduction margin.

Key Words
seismic strain rate, earthquake, faulting

Citation
Marliyani, G. I., Pramumijoyo, S., & Helmi, H. (2021, 08). Active tectonic regime of Java Island, Indonesia from seismic strain rate analysis. Poster Presentation at 2021 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology