A New Method for Measuring Time-Dependent Deformation: Persistent-Scatterer INSAR

Stanford University, Stanford CA

Investigators

Abstract

Interferometric SAR (InSAR) measurements have proven invaluable for study of active volcanism, earthquakes, landslides, and other geophysical phenomena. Yet temporal and spatial decorrelation limit its applicability to mostly dry, sparsely vegetated areas, while these hazards are distributed globally. The permanent scatterers technique, which focuses on resolution elements whose echo is dominated by a single bright scatterer, is a new method that can eliminate these sources of noise. This method has proven successful when applied to urban areas where man-made structures are dominant scatterers, but has been less successful over natural terrains, including most volcanoes, faults, and landslides. We have developed a new analysis approach that identifies many more stable pixels in natural terrains than are found using published persistent scatterer methods. We propose to further develop the persistent scatter method as a means to fully exploit the existing archive of spaceborne radar data. We will apply the method to areas where new data can best contribute to our understanding of geophysical processes, including one volcanic area (Mt. St. Helens), one tectonic area (Denali Fault), and one landslide area (Castagnola, Italy). Natural hazards remain dangerous and expensive challenges to society; their study is limited in most of the world by the scarcity of geophysical data. Improved persistent scattering analysis methods will result in more comprehensive remote sensing coverage from existing radar systems, and lead to a more complete understanding of earthquakes, volcanoes, and landslides. The proposal will support the work of a senior Ph.D. student, contributing to the training of a new generation of Earth scientists. Our software will be made available to all interested researchers.