GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 1.1 - POSTER GNGTS 2023 The first absolute gravity and height reference network in Sicily F. Greco 1 , G. Berrino 2 , F. Riguzzi 3 , A. Mazzoni 4 , M. Amendola 4 , D. Contrafatto 1 , G. Dardanelli 5 , M. Lo Brutto 5 , A. Maltese 5 , A. Messina 1 , L. Mirabella 1 ,G. Ricciardi 2 , L. Samperi 1 1 INGV, sez. Osservatorio Etneo, Catania 2 INGV, sez. Osservatorio Vesuviano, Napoli 3 INGV, sez. Osservatorio Nazionale Terremoti, Roma 4 DICEA, Università La Sapienza, Roma 5 DICAA, Università di Palermo In this poster we present the implementation and the surveys performed to establish a new reference gravity and elevation network in Sicily with the aim to provide new reference systems useful for all the scientific and technological activities related to the gravity field and to the proper definition of a modern height system in this region. This network belongs to the under construction new Italian Reference Gravity Network (G0) that is part of the INGV Project Pianeta Dinamico, Task S2, during the period 2019-2022. The Sicilian network encloses 5 stations (Catania, Centuripe, Milazzo, Noto, and Palermo), evenly distributed forming a large mesh network which roughly covers the entire Sicily (Fig.1). All absolute stations are hosted inside structures that guarantee protection for the instrumentation during the measurements and the necessary power supply (Greco et al., 2021a). In addition to the absolute gravity value, at each station, the vertical gravity gradient and the gravity difference ( Δ g) between the indoor absolute gravity and an outdoor satellite station were also measured (Greco et al., 2021b). Gravity measurements were carried out between the end of 2021 and the 2022 with the Microg LaCoste FG5#238 and the Scintrex CG-6 gravimeters for absolute and relative measurements, respectively. Gravity data have been corrected for known effects ensuring the reliability and accuracy at the µGal level. The coordinates and the orthometric heights were at the same time measured with mixed terrestrial and satellite local networks at each site (Fortunato et al., 2020). The precise coordinates obtained after the adjustments were useful to post-process the absolute gravity data and to refer all the gravity measurements presented in this work to the equipotential surface of the gravity field.