Experimental research into emission of ultra fine dusts as harbingers of volcanic –seismic events

Abstract

Usually the history of a volcano is marked by the alternation of brief intervals of eruptive activity and long periods of apparent inactivity. During the long periods of pseudo-inactivity, there are evident symptoms that the volcano is still active, e.g. fumaroles, hot springs and gaseous emissions. The variation in intensity of previous phenomena may be used for a possible forecasting of forthcoming volcanic-seismic events. The aim of the present research was to use the variation in emissions of ultra fine dusts in the period of pseudo–inactivity to obtain an index able to forecast the possible volcanic eruption, or volcanic seismic event, some time before it occurs. Thus we conducted a long-term monitoring campaign near some volcanic faults on the slopes of Mt. Etna (Sicily) measuring: - variation in concentration of ultra fine dusts (PMx) in the air; - meteoclimatic parameters such as temperature, relative humidity, direction and intensity of wind; - seismic parameters such as magnitude and length of seismic events. From the systematic analysis of data acquired over two years of monitoring, it was possible to develop composite parameters termed Seismicity of Period (Im) and “Forced Peak” (FP). Correlating MI, FP, and the measured mean daily concentration of PM10 in the air, it was possible to determine the required index able to forecast possible seismic volcanic events. Research is currently in progress to refine the index which could be utilized not only to forecast possible seismic volcanic events, but also as a key to give early warning to the Civil Protection Agency so that they can be ready in time should an eruptive event occur.