Analysis of subsidence using TerraSAR-X data: Murcia case study

This paper presents an analysis of the performance of the Coherent Pixel Technique for urban subsidence monitoring using TerraSAR-X data. Repeated observations for the period comprised between July 2008 and September 2009 have been used. For this purpose the city of Murcia has been selected as a test-site because it is affected by subsidence due to groundwater exploitation. The obtained results are compared with those obtained from ERS/ENVISAT data belonging to the same period and validated with pre-existing information. Subsidence data reveal average rates of subsidence for the whole area up to − 5 mm/year with local values that reach − 35 mm/year. These results are analyzed with respect to the main factors that control subsidence mechanisms: the thickness of the compressible layer, the presence of pumping wells, and the water table variation. Finally a local analysis of several buildings and infrastructures is presented. Therefore the usefulness of X-band radar technology, not only to improve the knowledge of this kind of regional phenomenon, but also to study its effects on local areas such as buildings and infrastructures is demonstrated.This study was partially funded by the Spanish Ministry of Science and Technology and EU FEDER (Projects TEC-2008-06764 and CGL-2009-08457) and by the Generalitat Valenciana (Project ACOMP/2010/082), as well as by the Spanish Geological and Mining Institute (IGME) with the collaboration of the Regional Government of Murcia. The TerraSAR-X images were provided by DLR in the framework of the scientific project GEO0389. ERS and ENVISAT data were provided by ESA in the framework of the CAT1 project 2494