GNGTS 2017 - 36° Convegno Nazionale

28 GNGTS 2017 S essione 1.1 Here we present an up-to-date high resolution picture of the ongoing crustal deformation field of southern Italy, based on an extensive combination of continuous and episodic GNSS observations carried out since 1994 (Fig. 1). The analyzed continuous GNSS observations have been collected at 120 stations (with more than 2.5 years of observations) which belong to various networks developed by different institutions and agencies for crustal deformation monitoring and commercial applications such as mapping and cadastral purposes: INGV (INGV RING Working Group, 2016), Agenzia Spaziale Italiana (http://geodaf.mt.asi.it ), Netgeo (http://www.netgeo.it) , Italpos (http://it.smartnet-eu.com) and Regione Calabria (http:// gpscalabria.protezionecivilecalabria.it) . The episodic measurements have been collected at 109 benchmarks during repeated surveys carried out in the last 2 decades; 83 benchmarks belong to the local networks extensively covering eastern Sicily and managed by INGV, while the remaining benchmarks, located in central and western Sicily, belong to the “IGM95 geodetic network” developed at the end of the last century by the Istituto Geografico Militare network (IGM, www.igmi.org ). To improve the overall configuration of the network and tie the regional measurements to an external global reference frame, data coming from more than 20 continuously operating global tracking stations, largely from the IGS and EUREF permanent networks, have been introduced in the processing. We have not taken into account all the continuous GNSS stations installed on Mt. Etna because their motion is affected by sub-crustal magma movements (see Spampinato et al. , 2015 and references therein for an overview). Raw GNSS observations have been reduced to loosely constrained daily solutions by using the GAMIT/GLOBK software packages (Herring et al. , 2015) and following the approach described in Palano (2015). In order to adequately study the crustal deformation field over the investigated area, the estimated GNSS velocities have been referred to a fixed Eurasian reference frame as well as Fig. 1 - Simplified sketch map of southern Italy. Analyzed GNSS stations are reported as red and blue points for continuous and episodic benchmark, respectively.