FIFTEEN YEARS OF ERS AND ENVISAT DInSAR OBSERVATIONS AT MT. ETNA (ITALY) BY USING THE SBAS APPROACH

Abstract

We exploited the Small BAseline Subset (SBAS) technique and computed ground displacement maps and time series by inverting 283 interferograms generated from the ascending and 289 from the descending orbits to reveal Mt. Etna surface deformation from 1992 to 2006. Our analysis shows that the volcano experienced magmatic inflation/deflation and radial spreading of the west, south and east flanks. In particular, the summit area vertical deformation inverted its sign after 2000 and clearly shows a deflation effect related to the 2001 and 2002 eruptive and seismic events. On the contrary, the horizontal signals revealed on the eastern and western flanks present significant and consistent motions toward east and west, respectively, during the investigated interval. Overall, the presented results show the complex and articulated deformation behavior of Mt. Etna and remark the possible coexistence of both gravity and magma forcing