Volcanic surface changes by Pleiades satellite data.

Active volcanic areas are frequently affected by surface changes due to erupted products such as lava flows or fallout deposits. Remote sensing makes it possible to overcome field difficulties of inaccessible areas and allows measurements of areas and volumes of the erupted material. In this communication, stereo images pairs of the Pleiades satellites acquired on the volcanic areas of Mt. Etna and Stromboli have been taken into consideration. The stereo pairs of the Pleiades (1&2 and 2&3) were processed by using the NASA Ames Stereo Pipeline (ASP), an open source automated geodesy suite of stereophotogrammetry tools that process stereo images with or without accurate camera pose information. A 3D point cloud is the output obtained through a triangulation combining ephemeris/spacecraft attitude information, sensor model. Comparing the resulting surfaces, the areas and volumes affected by changes are calculated. These results, discussed and compared with available field data, can help to better understand the impact of the event and provide indications useful in a territory planning aimed to mitigate the effects of such calamitous events.