17:15 〜 18:45
[SVC26-P21] Surface deformation of the Semeru volcano constrained by InSAR measurements
キーワード：Surface deformation, InSAR, Volcanic unrest, Time series
Multiple eruptions have been documented following the 2021 eruption of Semeru Volcano. The summit is the highest peak on Java Island, Indonesia, with eruptive activity repeated almost every year. An inherent challenge in monitoring active volcanoes is the insufficient infrastructure for on-site data collection. Hence, observing the erratic deformation of these objects provides valuable insights into underlying activity and structure. Interferometric Synthetic Aperture Radar (InSAR) is an effective instrument for calculating active deformation area and estimating its source (Elliot et al., 2016). This study introduces the results of surface deformation observations using geodetic imaging over 3 years and utilizing hundreds of C-band SAR interferograms.
InSAR time series processing based on the new small baseline technique is applied to compensate for decorrelation (Aditiya and Ito, 2023), incorporating atmospheric corrections (e.g., Jolived et al. 2011). We applied a spatio-temporal filter to reduce residual noise for velocities and time series, respectively. Moreover, atmospheric, topography, and solid earth tide corrections were applied (Yunjun et al., 2019). As the results of the time series point out, there is a dynamic change around the summit that takes place throughout each eruption. The findings indicate that in the area affected by the lava flow on the southeast side, there was a substantial decrease in velocity, with an average velocity of -10 cm/yr. Meanwhile, the west side showed variation with an upward and downward rate of 0.39 and -0.02 cm/yr, respectively. We decomposed multi-geometry InSAR results to obtain quasi-horizontal and quasi-vertical components, respectively (e.g., Fuhrmann and Garthwaite, 2019). Furthermore, we propose combining some solutions to define deformation source shapes of complex deformation patterns.
InSAR time series processing based on the new small baseline technique is applied to compensate for decorrelation (Aditiya and Ito, 2023), incorporating atmospheric corrections (e.g., Jolived et al. 2011). We applied a spatio-temporal filter to reduce residual noise for velocities and time series, respectively. Moreover, atmospheric, topography, and solid earth tide corrections were applied (Yunjun et al., 2019). As the results of the time series point out, there is a dynamic change around the summit that takes place throughout each eruption. The findings indicate that in the area affected by the lava flow on the southeast side, there was a substantial decrease in velocity, with an average velocity of -10 cm/yr. Meanwhile, the west side showed variation with an upward and downward rate of 0.39 and -0.02 cm/yr, respectively. We decomposed multi-geometry InSAR results to obtain quasi-horizontal and quasi-vertical components, respectively (e.g., Fuhrmann and Garthwaite, 2019). Furthermore, we propose combining some solutions to define deformation source shapes of complex deformation patterns.