Time-Series InSAR Monitoring of Ground Deformation along the Baribis Fault Using LiCSBAS Muhammad Rakha Fadhila, Dwi Lestari
a) Undergraduate Student, Geodetic Engineering, Universitas Gadjah Mada, Indonesia
*muhammad.rakha1803[at]mail.ugm.ac.id
b) Associate Professor, Geodetic Engineering, Universitas Gadjah Mada, Indonesia
Abstract
The Baribis Fault a significant seismic threat running through Javas densely populated northern regions has yet to be mapped with a comprehensive 2D deformation analysis combining both ascending and descending InSAR data To better understand this risk our study uses time-series Interferometric Synthetic Aperture Radar InSAR to create a detailed map of its surface deformation We analysed Sentinel-1 imagery from 2017 to 2023 using the Small Baseline Subset SBAS technique within the open-source LiCSBAS platform with further analysis performed in Jupyter Notebook By combining data from ascending and descending satellite paths we decomposed the line-of-sight displacement into true vertical and horizontal East-West ground motion The accuracy of our results was then confirmed by comparing them against measurements from two nearby CORS stations CBTU and CTGR yielding a Root Mean Square Error between 509 and 534 cm Our analysis reveals complex ground motion vertical displacement rates range from -864 to 32 mmyr showing uplift in the north and nearly subsidence in the south while horizontal velocities range from -86 to 106 mmyr indicating a clear left-lateral strike-slip pattern Beyond providing the first comprehensive 2D deformation map for this critical fault this research highlights the practical power of a fully open-source workflow It shows how community-driven tools and free satellite data make advanced geodetic monitoring more accessible empowering local institutions to conduct their vital hazard assessments This work ultimately demonstrates how collaborative open science in remote sensing can directly contribute to building more resilient communities
Keywords: Baribis Fault, Deformation, InSAR, LiCSBAS, Open Science, SBAS
