Environmental Engineering Reference
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and gave rise to the grey clay (Campanian ignimbrite), while subsequent eruptions
have produced the yellow tuff that forms the base rock for the city of Naples. At
Ischia volcanism produced the green tuff.
4.8.3 The Etna volcano: activity, soils and landscape
Mount Etna, located in eastern Sicily, reaches a height of about 3300 m asl. The
active summit craters are closed westward of Bove Valley, a structure of collapse
depth 1000 m, 7 km long and 5 km wide. The eruptions occur from the summit
craters (Northeast Crater, Voragine, Bocca Nuova, Southeast Crater) and along the
flanks of the volcano. Since the late 1970s, summit eruptions have increased in
intensity, with extremely violent paroxysmal eruptive episodes after 1995, culmi-
nating in 2005 with 120 events, many of which have affected the southeast of the
crater (Behncke and Neri, 2003; Branca and Del Carlo, 2004) (Figure 4.6).
These episodes have generated lava fountains accompanied by abundant pyro-
clastic flows transported a few tens of kilometres from the volcano (Figure 4.7). In
addition to these intense manifestations, typically lasting less than 30 minutes, the
Etna eruptive activity has affected both sides of the southwestern (Bove Valley) and
Figure 4.6
MODIS image. On 21 July 2006, the Moderate Resolution Imaging Spectroradiome-
ter (MODIS) flying onboard NASA's Terra satellite captured this image as Sicily's Mount Etna
volcano emitted a faint plume of volcanic ash that blew away from the summit, towards the south-
west. NASA image courtesy the MODIS Rapid Response Team at NASA GSFC. The MODIS
Rapid Response Team provides daily images of Mount Etna
