A map for volcaniclastic debris flow hazards in Apennine areas surrounding the Vesuvius volcano (Italy)

Abstract

Volcaniclastic debris flows are dangerous natural phenomena that originate in volcanic areas not only during or shortly after an eruption but also during a period of volcanic quiescence, when heavy and/or persistent rains remobilize unconsolidated pyroclastic deposits. In Italy, one of the areas most affected by these phenomena is that of the Apennine Mountains which border the southern Campania Plain surrounding the Vesuvius volcano. Historical accounts record in these areas that more than 500 debris flow events occurred during the last five centuries. These events caused very dangerous consequences such as loss of life and serious damage to property. An example is the devastating event of Sarno of 5 May 1998 which caused the death of more than 150 people and considerable damage to villages located at the foot of the Apennine Hills. In order to contribute to the assessment and mitigation of the debris flow risk, we propose a zonation map that identifies the areas more prone to generation and invasion by volcaniclastic flows. This map is based on field investigations and morphometric analyses derived from a digital elevation model with spatial resolution of 10 meters.