GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.2 GNGTS 2024 acceleraton of the eastern fank confned to the main tectonic features. The Etna summit blow-up exposes in detail the Valle del Bove area which accommodated the lava fows studied here in detail through the DTS analysis and the resultant ground displacement vector computaton. This later at the 2018 - 2019 lava fow area shows a contractonal behavior typical of the cooling of young lava fows, suggestng that the thermal lava contracton is the main deformaton cause. Instead, the comparable amplitude of subsidence and eastward moton for the overlapping porton of 2011 - 2015 and August 2020 - July 2021 lava fows, suggests that the combined efect of old lavas load and recent lavas thermal cooling should be taken into account. Finally, DTS in the T1 period highlight clear uplif and eastward trends related to volcanic infaton, except for older lava fow where the global uplif is masked by subsidence related to the existng lava fows load on the substrate. DTS executed for the T2 period exhibit subsidence and eastward trends that accelerate afer the emplacement of new lava fows. These trends contrast only with the cyclic vertcal oscillatons recorded outside lava felds, refectng Etna’s breathing process. Figure 2 – Main outcomes for the Etna volcano area. From lef to right: ground displacement maps, resultant ground displacement vectors for the indicated areas within the fgure, and displacement tme series. Figure 3 shows the preliminary results of the Sangay volcano case study. Displacement maps show mainly westward and eastward directed movements of the western and eastern slopes, respectvely. In additon, on the western fank of the volcano, clear infaton can be seen, which contrasts with the subsidence recorded on the northern and southeastern fanks. The tme series performed along the N fank of the volcano, at the point indicated by the black triangle in the vertcal displacement map visible in Figure 3, shows a clear subsidence since early December 2021. Using radar signal intensity variaton analysis, it was possible to verify that the behavior can be associated with the cooling of the pyroclastc fow generated on November 28, 2021.