GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 1.1 GNGTS 2023 Geodetic strain rates and seismicity rates along the Apennines R. Nucci 1 , E. Serpelloni 2 , L. Faenza 2 , A. Garcia 2 , M.E. Belardinelli 1 1 Dipartimento di Fisica ed Astronomia - Università di Bologna, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia - Bologna, Italy Abstract The Apennines are a tectonically active belt that was the site of strong historical earthquakes, such as the recent L’Aquila (2009) and Amatrice-Visso-Norcia seismic sequences (2016-2017). Interseismic strain build-up is now precisely measurable using space geodetic techniques. The increasing density of global navigation satellite system (GNSS) stations allows us to estimate the horizontal strain rate with greater spatial resolution than in the past. Here we investigate the correlation between horizontal geodetic strain rates and seismicity rates through the Apennines, evaluating possible implications for seismic hazard assessment. We use a new GPS velocity field for Italy (Fig. 1), derived from Serpelloni et al. (2022), and we analyze the deformation rates through the computation of the horizontal strain rate field. We employ different algorithms for this computation, already described in the scientific literature (Handwerger et al. , 2018, Shen et al. , 2015 and Tape et al., 2009), and discuss strengths and limitations of each one. We then follow the approach of Stevens and Avouac (2021), in order to investigate the relationship between observed strain rates and seismicity rates along the Apennines, testing the different hypotheses that sustain the approach.