Application of Satellite Interferometry to the Detection of Surface Deformation in the Salton Sea Geothermal Field, California

Abstract

A permanent scatterers interferometric synthetic aperture radar (PSInSARTM) technique was applied to detect and quantify surface deformation in the Salton Sea geothermal field, in the Imperial Valley of southern California. This field is located in an agricultural area, where traditional differential interferometry (DInSAR) does not produce results. The data analyzed were collected by the Canadian Radarsat-1 satellite over a two-year period (2006-2008), from both ascending and descending orbits. This makes it possible to decompose the observed motion, measured in the line-of-sight (LOS) to the satellite, into vertical and west-east horizontal components of the surface movements. The satellite results are in very good agreement with measurements from ground-based leveling surveys carried out within the field. Measurements from the regional GPS PBO network were used to constrain both the satellite and the leveling observations. It is thus demonstrated that PSInSARTM is a viable technique for monitoring surface deformation in geothermal fields.