Land subsidence characteristtics of Bandung Basin as revealed by ENVISAT ASAR and ALOS PALSAR interferometry

In this study, characteristics of land subsidence in Bandung Basin, Indonesia was estimated using the C-band ENVISAT ASAR and the L-band ALOS PALSAR data, acquired between 2002 to 2008 and 2007 to 2011, respectively. The software, GEOS-APSI (Advanced Persistent Scatterer Interferometry), was used to map the long term land displacement. GEOS-APSI is an in-house developed software by GEOS at UNSW for Interferometric SAR Persistent Scatterer Interferometry. Several subsidence zones were identified in the basin including areas in Cimahi, Dayeuh Kolot, Rancaekek, and Solokan Jeruk. Subsidence with a maximum of 250 mm/yr was observed in some of the zones. The results were validated with six epochs of GPS survey between 2002 and 2010. The standard deviation of difference in subsidence between InSAR and GPS measurements for ENVISAT ASAR and ALOS PALSAR was 13 mm/yr and 22 mm/yr, respectively.