Abstract
Ground subsidence due to groundwater extraction is a severe problem of many cities in depositional plains all around the world. In the Kanto plain, where the capital region of Japan is situated, ground subsidence with a few centimeter per year has occurred in recent years especially in the northern part of the Kanto plain. However, the detailed spatial distribution of subsidence has not been revealed yet. In this study, we estimated the spatial distribution of ground subsidence of the northern Kanto plain from August 2006 to February 2011 by persistent scatterer SAR interferometry. Persistent scatterer SAR interferometry is a satellite-based remote sensing method to map surface displacement, and has an advantage for mapping displacement in a broad area with a fine spatial resolution. The estimated ground subsidence was comparable with GPS and leveling data. Moreover, the spatial pattern of ground subsidence was likely correlated with geological structure of the area. Our results demonstrate the effectiveness of persistent scatterer SAR interferometry for monitoring ground subsidence.
