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

Abstract

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.