Electronic Theses and Dissertation

Kabupaten aceh singkil termasuk wilayah rawan bencana gempa bumi, yang diakibatkan oleh kondisi geotektonik dan geologisnya yang terletak pada zona megathrust subduksi lempeng indo-australia dan eurasia. pada 16 januari 2023, pukul 05:30 wib, terjadi gempa dengan kekuatan 6,2 mw dengan kedalaman 23 km yang menjadi gempa terbesar yang dirasakan aceh singkil pada tahun 2023. penelitian ini memanfaatkan metode multitemporal dinsar (differential interferometry synthetic aperture radar) untuk mengamati deformasi akibat gempa pada fase pre-seismic, co-seismic, dan post-seismic. metode ini memanfaatkan citra sentinel-1a yang mampu mengidentifikasi deformasi permukaan dengan akurasi tinggi, dalam ukuran cm-mm. pengolahan data dilakukan menggunakan software snap 9.0.0, snaphu, quantum gis, dan microsoft excel. hasil penelitian menunjukkan adanya deformasi maksimum berupa kenaikan tanah (uplift) berdasarkan los (line of sight) sebesar 10,1 cm untuk pre-seismic di kecamatan kotabaharu, 16,8 cm untuk co-seismic di kecamatan danau paris, dan 0,36 cm untuk post-seismic di kecamatan singkil utara. sedangkan deformasi minimum berupa penurunan muka tanah (subsidence) berdasarkan los sebesar -4,1 cm untuk pre-seismic di kecamatan danau paris, -3,2 cm untuk co-seismic di kecamatan suro, dan -0,35 cm untuk post-seismic di kecamatan singkil. dari penelitian ini, terlihat bahwa deformasi maksimum berupa uplift mengalami peningkatan signifikan pada fase co-seismic, sedangkan deformasi minimum berupa subsidence mengalami penurunan signifikan pada fase pre-seismic.

Aceh Singkil Regency is prone to earthquake disasters due to its geotectonic and geological conditions, located in the Megathrust Subduction Zone between the Indo-Australian and Eurasian Plates. Historically, it experienced a magnitude 8.6 earthquake followed by a tsunami on March 28, 2005. The earthquake on January 16, 2023, at 05:30 WIB, had a magnitude of 6.2 Mw, with an epicenter 47 km southeast and a depth of 23 km. Research on deformation is needed to identify areas that have experienced surface changes and the extent of those changes. This information can inform disaster mitigation steps. In this study, the author uses the multitemporal DInSAR (Differential Interferometry Synthetic Aperture Radar) method to observe potential deformation caused by the earthquake during the pre-seismic, co-seismic, and post-seismic phases. This method utilizes Sentinel-1A imagery, which can identify surface deformation with high accuracy, in the range of cm-mm. The software used for data processing includes SNAP 9.0.0, SNAPHU, Quantum GIS, and Microsoft Excel. The study results show maximum deformation in the form of land uplift based on Line of Sight (LOS) of 10.1 cm for pre-seismic in Kotabaharu District, 16.8 cm for co-seismic in Danau Paris District, and 0.36 cm for post-seismic in North Singkil District. The minimum deformation in the form of land subsidence based on LOS is -4.1 cm for pre-seismic in Danau Paris District, -3.2 cm for co-seismic in Suro District, and -0.35 cm for post-seismic in Singkil District. Thus, the study shows that significant uplift occurred during the co-seismic phase, while significant subsidence occurred during the pre-seismic phase.