High-resolution seismic imaging of the Pian di Neve Glacier on the Adamello Massif (Italy)

Active seismic investigations, generally employed to image the earth interior, are also widely applied in glaciology to map the thickness of glaciers and to study the basal sediment properties. In this work we present the results of a 1-km multichannel seismic survey carried out on the Pian di Neve, a high altitude glacier located in the Adamello massif (Italy), with the purpose to image the glacier bottom and obtain the ice thickness profile. The Pian di Neve occupies a 18-km2 plateau at an altitude of between 3100 and 3400 m, and together with the adjacent Mandrone glacier forms the largest glacier mass in the Italian Alps. From the maximum Little Ice Age extension to present, these two glaciers lost about 36% of their total area. The seismic survey evidenced an ice thickness ranging from 170 m to 270 m and the presence of a relatively thick layer of sediments at the bottom. Comparison with previous investigations seems to indicate that, in the last 50 years, the ice thickness in the survey area has not significantly changed. This evidence is contrary to the general retreat trend and could be due to a sort of thermal inertia in this glacial accumulation area.