The use of interferometric SAR in a study of reservoir induced crustal deformation

Interferometric synthetic aperture radar (In-SAR) has been used effectively in studies of small surface elevation changes due to various phenomena such as earthquakes, volcanoes, and ice movement. The interferometric technique involves coherently combining multiple images of an area to obtain estimates of the surface topography, and any changes to the topography that might have occurred between observations. This report outlines its intended use in a study of reservoir induced crustal deformation. Observations made by the European Space Agency´s two imaging radar satellites over the site of the Katse Reservoir in Lesotho are reduced to interferograms, and a statistically significant local phase signature in these interferograms may be interpreted as the crustal deformation field associated with the loading effect of the added water mass. A GIS is used to integrate and analyse the data so as to provide input to a mathematical model used for determining crustal elastic thickness