GNGTS 2013 - Atti del 32° Convegno Nazionale

Conclusion and discussion. A new unrest phase started in 2004 and is followed by our measurements since 2009. It involves large geochemical signatures, with increase of several volcanic gases, with relatively minor ground deformation and seismicity. It is consistent with an extensive fracturing of the caldera volume, caused by past unrests, with a consequent increase of the connection between deep fluids and shallow aquifers. This implies we should expect, in the future, less prominent uplift and seismic events, and more marked geochemical indicators as eruption precursors. A continuous, multi-gas geochemical monitoring as the one we developed, is then even more crucial for volcano monitoring, inter- pretation and forecast. This innovative methodology of continuous monitoring, which does not replace the traditional sampling using vial, allowed us to acquire more frequent data of gas composition in the fumarolic and degassing area of Pisciarelli. 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