ANALYSIS OF THE 1992-2010 DYNAMIC DEFORMATION AFFECTING THE YELLOWSTONE CALDERA

摘要

We analyze the temporal evolution of the deformation affecting the Yellowstone (Wyoming, U.S) complex volcanic system in the 1992-2010 time period. This work represents, at our knowledge, the first attempt at retrieving through differential synthetic aperture radar (DInSAR) techniques long-term deformation time-series at the Yellowstone Caldera. This is due to the presence of severe temporal decorrelation noise in the differential interferograms, which limit the overall performances of the DInSAR technique, especially with respect to phase unwrapping (PhU) operations. Accordingly, to increase the number of the investigated points in low coherent zones, we complement PhU operations with a space-time regiongrowing method. The presented results, obtained by applying the Small Baseline Subset (SBAS) DInSAR technique to a data set composed of 21 ERS and 22 ENVISAT SAR images, clearly demonstrate the validity of the proposed method.