Fig. 1: La Fossa cone and highlighted regions of interest.

A The shaded-relief map overview shows the nested crater regions, with the deepest crater being Gran Cratere. Regions highlighted are the flank collapse area on the north flank, including Forgia Vecchia (FV) (shaded in green, labeled “C”), landslide scarp, tension cracks, the area of intense alteration, Central Fumarolic Zone (CFZ; shaded in yellow, labeled “D”), the Outer Fumarolic Zone (OFZ) (shaded in blue), the collapsed slope in the northeast (1988 landslide, shaded red, labeled “E”), and the small and most recent landslide (2010 debris flow, shaded in pink). The triangles represent the camera’s direction for the photos taken in (C–E). B Shaded-relief map of Vulcano Island, with La Fossa cone outlined by a black box. The inset shows the location of Vulcano (highlighted in red) within the Aeolian Archipelago, north of Sicily. C Photograph of the northern flank, taken from the base of La Fossa facing S-SE. D Photograph of the fumarole field, taken from the southern crater rim facing the N-NE. E Photograph of the 1988 landslide scar, taken offshore facing S-SW.