DYNAMIC DEFORMATION OF ETNA VOLCANO OBSERVED BY SATELLITE RADAR INTERFEROMETRY

Satellite radar interferometry of Mt. Etna volcano, Sicily, Italy, rev eals a sequence of deformation characterized by deflation during the e nd of the 1993 eruption, inflation from 1993-1995 with an increase in the inflation rate immediately before its resumed eruptive activity in late 1995. This was followed by very low deformation levels during th e following year. The source of the deformation changed from a depth o f 9 km during deflation to more than 11-14 km during the subsequent in flation, consistent with a model in which deflation at shallower level s is followed by inflation at greater depth as the volcano system rech arges from below before its next eruption. This study demonstrates tha t radar interferometry provides an important contribution towards unde rstanding the dynamic deformation of volcanoes. By revealing large sca le changes in their pre-eruption deformation rates, radar interferomet ry could play an important role in volcano eruption monitoring.