Volcanic activity analysis of Mt. sinabung in Indonesia using InSAR and GIS techniques

Sinabung volcano in Indonesia is a part of the Pacific Ring of Fire, formed due to the subduction between the Eurasian and the Indo-Australian plate. We study the deformation of Sinabung volcano using ALOS/PALSAR interferometric synthetic aperture radar (InSAR) images acquired from Feb. 2007 to Jan. 2011. Based on multi-temporal InSAR processing, we have mapped the ground surface deformation before, during, and after the 2010 eruption. During the 3 years before the 2010 eruption, the volcano inflated at an average rate ~1.7 cm/yr with marked higher rate of 6.6 cm/year during the 6 months prior to the 2010 eruption. The inflation is constrained to the top of the volcano. Since the 2010 eruption to Jan. 2011, the volcano has subsided for about 3 cm. The observed inflation and deflation are modeled with a Mogi and Prolate spheroid source. The source of inflation is located about 0.3-1.3 km below sea level directly underneath the crater. On the other hand, deflation source is modeled about 0.6-1.0 km depth with coeruption period. The average volumetric change was about from -2.7×10^-5 to 1.9×10^-6 km3/yr during the deformation event. Modified Laharz model compare to Landsat-7 ETM+ image through supervised classification method. We interpret the inflation was due to magma accumulation at a shallow reservoir beneath Sinabung. Pyroclastic flow´s inundation area is highly matched between two different methods with about 86 % common region inserting for deflation pattern of volume by Mogi model.