Publication Date:
2023-12-04
Description:
In 2004, the DINEV project started in the Campi Flegrei - Vesuvius volcanic areas (Scarpa et al., 2007). This research program belongs to the Centro Regionale di Competenza AMRA, supported by PON funds, Regione Campania. The project was designed to complement the seismic and geodetic monitoring system of the Osservatorio Vesuviano through the installation of a small network of seven borehole stations, each installed at a depth up to 200m and instrumented with a Sacks-Evertson volumetric strainmeter. Each borehole station is separated by several kilometres from other stations, and the network covers many strategical distances from Campi Flegrei and Vesuvius volcanoes.
The network of four borehole strainmeters in the Pozzuoli region permits us to examine subsurface magma movements and pressures associated with magma ascent, storage, and the recharge of shallow magma reservoirs, and with the response of surface faults to these changes. Strainmeters are recognized as the potential best short-and middle-term instruments for eruption forecasting. Their maximum utility is recognized in the measurement of deformation 170 signals with durations of hours to weeks, providing quantitative constraints on the depth of the pressure source in case of inflation or deflation, and the possible detection of ground deformation accompanying small pressure variations due to increased bubble formation, hydrothermal fluid motions, and/or magmatic ascent in prior to inflation episodes.
A recent uplift episode was initiated in Campi Flegrei in November 2004, shortly after the installation of the borehole strainmeters. Relevant strainmeter data have been collected and analysed from the instruments installed near Campi Flegrei caldera during the recent unrest episodes. In the period 2004-2005 strain, tilt and GPS data from Campi Flegrei indicate the onset of surface deformation that accompanied a low rate of vertical displacement that continued to 2006, corresponding to an 15 increase of CO2 emission.
This strain episode preceded caldera microseismic activity by a few months, as was observed also during a significant inflation episode in 1982. Other transient strain episodes occurred in October 2006, which were accompanied by a swarm of VT (Volcano-Tectonic) and LP (Long Period) events, in 2009, at the time of renewed gas emission activity at Solfatara, and again in March 2010, several minutes before a seismic swarm. The time scale of these transient strain events ranges from some hours to several days, putting tight constraints on the origin of ground uplifts at Campi Flegrei.
Keywords:
strain; Volcano deformation
Type:
Dataset
Format:
application/zip, 7 datasets
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