Eighteen years of GPS surveys in the Aeolian Islands (southern Italy): open data archive and velocity field

Alessandra Esposito Alessandra Esposito,Giuseppe Puglisi Giuseppe Puglisi,Vincenzo Sepe Vincenzo Sepe,Marco Anzidei Marco Anzidei,Enrico Serpelloni Enrico Serpelloni,Alessandro Bonforte Alessandro Bonforte,Mario Mattia Mario Mattia,Valentina Bruno Valentina Bruno,Grazia Pietrantonio Grazia Pietrantonio,Francesco Guglielmino Francesco Guglielmino

doi:10.4401/ag-6823

Alessandra Esposito Alessandra Esposito, Giuseppe Puglisi Giuseppe Puglisi + Show 8 more

Open Access

https://doi.org/10.4401/ag-6823

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Abstract

<p>Since the early 1970s, geodetic networks became a most important tool to monitor the present day deformations of the volcanic arc of the Aeolian Islands. The first benchmarks were installed in this region at Lipari and Vulcano Islands and the number of GPS benchmarks increased in time since the early ’90s. These networks were periodically surveyed in the frame of national and international geodynamic projects and for Civil Protection programs devoted to the mitigation of the volcanic hazard. The Istituto Nazionale di Geofisica e Vulcanologia (INGV) played a fundamental role in the realization and periodical reoccupation of these networks, with the goal to investigate the tectonic and volcanic processes, still active in this crucial area of the central Mediterranean. An updated GPS velocity map for this region, both for the horizontal and vertical component of land motion, with details for Lipari, Vulcano and Panarea Islands, is provided in this paper. The presented GPS velocity field also includes a set of additional discrete stations located in northern Sicily and Calabria together with data from the available CGPS networks active in southern Italy. Here we show the results from eighteen years of repeated GPS surveys performed in this region in the time span 1995-2013 and the open access AINET-GPS data archive, now freely available for the scientific community. Data will support scientific research and hopefully improve the assessment of volcanic and seismic hazard in this region.</p>

Highlights

The horizontal GPS velocity field at the regional scale of the Aeolian Islands, expressed with respect to a fixed Eurasian plate, shows a pattern characterized by lithospheric shortening from SE to NW, gradually decreasing from S to N (Figure 3, Table 2)
The continuous monitoring GPS stations (CGPS) networks provide continuous data to study the kinematics of this region, the dense local scale survey style GPS networks detail the deformation of local scale areas in such a complex and transitional region, at low costs and with high accuracy
Results are in agreement with previous studies, highlighting and detailing the kinematics of local active areas, thanks to the high number of GPS benchmarks located in this region

Summary

Introduction

GPS surveys represent a key tool to investigate geodynamic processes at the Earth’s surface and estimate volcanic and seismic strain in active areas, such as along faults or signals from magmatic injections at surface, occurring inside volcanic reservoirs [Dvorak and Dzurisin 1997, Anzidei et al 1998, Anzidei et al 2001, Anzidei et al 2005, Serpelloni et al 2005, Serpelloni et al 2006, Anzidei et al 2008, Tregoning and Rizos 2008, Esposito et al 2010, Patanè et al 2013, De Martino et al 2014, Ferranti et at. 2014, Baldi et al 2015]. The first pioneering GPS campaigns started in southern Italy in 1987 in the frame of the Wegener/Medlas-Calabrian Arc international projects [Kaniuth et al 1989] These were experimental in nature, they put the basis for the realization of the first regional geodetic networks for geophysical applications devoted to detect the current deformations rates in this active area of the Mediterranean basin which is placed across the African and Eurasian tectonic plates [Achilli et al 1993, Anzidei et al 1995]. 28 geodetic benchmarks have been established across the Aeolian Islands: 6 of these are located at Lipari, 9 at Vulcano and 9 at Panarea, while the remaining are placed at Alicudi, Filicudi, Salina and Stromboli Islands The former benchmarks of the EDM networks were upgraded and re-occupied using GPS receivers and included in the new networks. Because the GPS technique does not require the intervisibility between observation points, some benchmarks formerly located in uncomfortable and remote places (such as the top of hills) have been replaced with new benchmarks of easier access to facilitate GPS surveys [Bonforte and Guglielmino 2008]

GPS data Although the early GPS campaigns in the Aeolian

Combination of daily solutions and reference frame definition

Results

Discussion and conclusion