DINAMIKA DEFORMASI GUNUNG MERAPI PADA TAHUN 2018-2019 MELALUI PENGAMATAN INSAR

• Main Author: Fajar Adiwijaya, Raihan
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/61546
• Institution: Institut Teknologi Bandung

Merapi is a volcano with high activity in Indonesia. One of the recent activity was happened in May 21st 2018 with a phreatic erruption. Since then, the activity of Merapi is increasing until today. This research use Sentinel 1 data to observe the increase activity of Merapi. The SAR image product from Sentinel 1 can be developed into interferograms that can inform the event of deformation that happen in Merapi as the activity rises through time. We use GMTSAR to make interferograms and GACOS atmospheric model and atmospheric model constructed from DEM to correct the interferograms. The use of additional atmospheric model is due to the tropospheric delay which correlate with the elevation of Merapi contributes the error of the displacement in line of sight with the residue of the displacement error still can be found surrounding Merapi even after reduced with GACOS model. Layover happens in the eastern part of Merapi due to the high slope of the area, resulting some error that is shown with no color that represent no data. The high amount of vegetation also contributed to the high amount of decorrelation surrounding Merapi, making only the peak with no vegetation having a high value of coherence. From the processes we conducted, we got the dynamics of the activity of Merapi in the form of uplift and subsidence. Uplift detected before the phreatic eruption until June 2018 and July 2018 to October 2018. Subsidence detected after the phreatic eruption from June to July 2018 and September 2019 to October 2019.