GNGTS 2015 - Atti del 34° Convegno Nazionale

degrees, and they are not necessarily correlated to the sensor depth. The values obtained for MIRB using the sensor at the surface as a reference, show that the misalignment angle for the sensor located at z=31 m is quite large (120°), probably because its sensor was not aligned at all, while surprisingly, a good value of 7° is obtained for the deeper sensor, if we consider that the sensor lays at 126 m of depth. MSN borehole showed quite misaligned, with an angle of about 135°, while IMAA borehole sensor appears rotated in an opposite position of almost 180° respect to the surface sensor. Finally, ED01 showed a small misalignment angle of about 8° (Diez Zaldivar et al. , submitted). Considering the obtained values, the misalignment angle correction was applied on the recorded data of IMAA and MSN, so that the extracted waveforms (downloadable on NISBAS Event Waveforms site) are already corrected. For MIRB and ED01 stations, instead, the correction has to be applied after downloading the data from the Continuous Waveforms , in order to reduce errors in the analysis procedure. Conclusions. NISBAS was created with the aim of organizing, archiving, and providing access to seismological data recorded by coupled seismological accelerometers/seismometers installed at the surface and in boreholes. They represent a valuable resource of data that may be of interest for the scientific community. Through a web interface ( http://nisbas.crs.inogs. it ), the user can retrieve detailed information about the seismological stations as well as either download generic pieces of waveforms taken from the stream of continuous recordings or seismograms related to specific events. Acknowledgements. Version 1.0 of June 2015 was realized within the research project entitled “Progetto S2- 2014, Constraining Observation into Seismic Hazard. The project is the 3rd S2 Project funded in the frame of DPC (Dipartimento di Protezione Civile Nazionale) – INGV (Istituto Nazionale di Geofisica e Vulcanologia) agreements. It concerns the mid-long term Seismic Hazard Assessment in Italy, focussing in betterment that can be reached on two priority areas. References Ahern, T., Casey, R., Barnes, D., Benson, R., and Knight, T.; 2007. SEED Standard for the Exchange of Earthquake Data Reference Manual Format Version 2.4, http://www.fdsn.org/seed_manual/SEEDManual_V2.4.pdf. Attolico, A., Gallipoli, M.R., Harabaglia, P., Lapenna, V., Mucciarelli, M., Rosa, A.B.; 2010. A review of the activity of two accelerometric networks in Basilicata (Italy), Bulletin of Earthquake Engineering , 8(5) 1131-1140 Bragato, P.L., di Bartolomeo, P., Pesaresi, D., Linares, M.P.P., Saraò, A.; 2011. Acquiring, archiving, analyzing and exchanging seismic data in real time at the seismological research center of the OGS in Italy. 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Geophysical Journal International , 188(3), 1243-1254. NTC; 2008. Norme Tecniche per le Costruzioni, DM 14/01/2008, GU n.29 del 04/02/2008, Suppl. Ord. 30 (in Italian) Laurenzano G., E. Priolo, C. Barnaba, M.R. Gallipoli, P. Klin, L. Martelli, M. Mucciarelli, e M. Romanelli; 2013. Studio sismologico per la caratterizzazione della risposta sismica di sito ai fini della microzonazione sismica di alcuni comuni della Regione Emilia-Romagna. Atti del 32 Convegno Nazionale GNGTS, Tema 2, pp. 247-252. Laurenzano G., Priolo E., Barnaba C.; 2015. Site response estimation at Mirandola by virtual reference station. Convegno finale Programma Sismologico DPC-INGV, Poster Session, 4-5 giugno, Bologna (Italy) Luzi, L., Hailemikael, S., Bindi, D., Pacor, F., Mele, F., and Sabetta, F.; 2008. ITACA (ITalian ACcelerometric Archive): A Web Portal for the Dissemination of Italian Strong-motion Data. Seismological Research Letters , 79(5), 716–722, doi: 10.1785/gssrl.79.5.716 Pacor F., Paolucci, R., Luzi, L., Sabetta, F., Spinelli, A., Gorini, A., Nicoletti, M., Marcucci, S., Filippi, L., and Dolce, M.; 2011. Overview of the Italian strong motion database ITACA 1.0. Bulletin of Earthquake Engineering, 9(6), 1723–1739, doi: 10.1007/s10518-011-9327-6. GNGTS 2015 S essione 2.2 141