caa a22 4500 445846798 CHVBK 20180317145401.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s10518-011-9273-3 doi (NATIONALLICENCE)springer-10.1007/s10518-011-9273-3 Site effects observed in alluvial basins: the case of Norcia (Central Italy) [Elektronische Daten] [D. Bindi, L. Luzi, S. Parolai, D. Di Giacomo, G. Monachesi] In this work, we investigate the site amplification effects observed in the Norcia plain, Central Italy. Data from 30 selected local earthquakes (2 ≤ Ml ≤ 4.1) recorded by a temporary seismic network composed by 15 stations, are analyzed to determine the spatial variability of site effects. Both the Horizontal-to-Vertical spectral ratio and the Standard Spectral Ratio techniques are applied to estimate the site amplification effects. The results show that most of the sites in the valley are affected by strong amplifications (up to a factor of 20) in the frequency range 0.5-5Hz. The value of the fundamental frequency of resonance is strictly dependent on the location within the basin and on the sediment thickness. Strong amplifications also affect the vertical components. The time-frequency analysis performed on a station located inside the basin shows the presence of a large spectral amplitudes after the S-wave phase, not observed on a station located on the bedrock, suggesting the presence of locally generated wave trains. Then, in agreement with earlier observations for other alluvial basins in Central Italy, 2D-3D effects play an important role in determining the site amplification effects in Norcia. Springer Science+Business Media B.V., 2011 Site effects nationallicence Alluvial basin nationallicence Horizontal-to-vertical spectral ratio nationallicence Standard spectral ratio nationallicence Bindi D. GFZ German Research Centre for Geosciences, Centre for Disaster Management and Risk Reduction Technology (CEDIM), Helmholtz Centre Potsdam, Telegrafenberg, 14473, Potsdam, Germany aut Luzi L. Sezione di Milano Pavia, Istituto Nazionale di Geofisica e Vulcanologia, Via Bassini 15, 20133, Milan, Italy aut Parolai S. GFZ German Research Centre for Geosciences, Centre for Disaster Management and Risk Reduction Technology (CEDIM), Helmholtz Centre Potsdam, Telegrafenberg, 14473, Potsdam, Germany aut Di Giacomo D. GFZ German Research Centre for Geosciences, Centre for Disaster Management and Risk Reduction Technology (CEDIM), Helmholtz Centre Potsdam, Telegrafenberg, 14473, Potsdam, Germany aut Monachesi G. Centro Nazionale Terremoti, Istituto Nazionale di Geofisica e Vulcanologia, Ancona, Italy aut Bulletin of Earthquake Engineering Springer Netherlands 9/6(2011-12-01), 1941-1959 1570-761X 9:6<1941 2011 9 10518 https://doi.org/10.1007/s10518-011-9273-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10518-011-9273-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bindi D. GFZ German Research Centre for Geosciences, Centre for Disaster Management and Risk Reduction Technology (CEDIM), Helmholtz Centre Potsdam, Telegrafenberg, 14473, Potsdam, Germany aut NATIONALLICENCE 700 1- Luzi L. Sezione di Milano Pavia, Istituto Nazionale di Geofisica e Vulcanologia, Via Bassini 15, 20133, Milan, Italy aut NATIONALLICENCE 700 1- Parolai S. GFZ German Research Centre for Geosciences, Centre for Disaster Management and Risk Reduction Technology (CEDIM), Helmholtz Centre Potsdam, Telegrafenberg, 14473, Potsdam, Germany aut NATIONALLICENCE 700 1- Di Giacomo D. GFZ German Research Centre for Geosciences, Centre for Disaster Management and Risk Reduction Technology (CEDIM), Helmholtz Centre Potsdam, Telegrafenberg, 14473, Potsdam, Germany aut NATIONALLICENCE 700 1- Monachesi G. Centro Nazionale Terremoti, Istituto Nazionale di Geofisica e Vulcanologia, Ancona, Italy aut NATIONALLICENCE 773 0- Bulletin of Earthquake Engineering Springer Netherlands 9/6(2011-12-01), 1941-1959 1570-761X 9:6<1941 2011 9 10518 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer