INGV strong-motion data web-portal: a focus on the Emilia seismic sequence of May-June 2012

Abstract

In Italy, strong-motion monitoring was started in 1972 by different Institutions, although mainly through Ente Nazionale per l'Energia Elettrica (ENEL; Italian National Electricity Company) and Dipartimento della Protezione Civile (DPC; Italian Department of Civil Protection), with different purposes. These included permanent acceleromet- ric monitoring and temporary monitoring during seismic se- quences or before permanent installation. Today, the National Accelerometric Network (RAN; Rete Accelero- metrica Nazionale) [Gorini et al. 2010, Zambonelli et al. 2011] is operated by the DPC and consists of 464 digital sta- tions. These are distributed throughout the whole national territory, with a prevalence for areas of major seismicity. In 2006, the INGV began strong-motion monitoring, by installing 22 accelerometric stations in northern Italy (RAIS; Rete Accelerometrica Italia Settentrionale; Accelerometric Network of Northern Italy; http://rais.mi.ingv.it/). In 2008, the monitoring was extended to a national scale: this effort led to the installation of 105 accelerometers, collocated with the velocimetric sensors, in selected Rete Sismica Nazionale (RSN; National Seismic Network) sites [Amato and Mele 2008] that are managed by the Centro Nazionale Terremoti (CNT; National Earthquake Centre). Overall, the 127 strong- motion stations that form the INGV Italian strong-motion network homogeneously cover the whole Italian territory. The progress achieved in Italy in the field of strong-mo- tion monitoring and strong-motion data archiving and dis- semination was illustrated in a recently published special issue of the Bulletin of Earthquake Engineering [Luzi et al. 2010]. The strong-motion data recorded by the RAN have been distributed and are available on request to the DPC and to the Italian Accelerometric Archive (ITACA), as the Italian strong-motion database (http://itaca.mi.ingv.it/) [Pacor et al. 2011a], which has been updated with records to 2009. The INGV strong-motion data are archived in real-time and dis- tributed through the European Integrated Data Archive (EIDA; http://eida.rm.ingv.it/) web portal. Recently, an INGV working group developed the first version of a web portal with the aim of archiving, processing and distributing accelerometric data recorded by permanent and temporary INGV stations. This web portal (www.mi. ingv.it/ISMD/; Figure 1, top panel) is composed of two main modules: the former is known as the INGV Strong Motion Data (ISMD, www.mi.ingv.it/ISMD/ismd.h tml/; Figure 1, bottom left panel) and has as its main scope the analyse and distribution in quasi-real time (a few hours after event oc- currence) of the uncorrected accelerometric data, and the related metadata obtained after an automatic processing pro- cedure. This latter, known as the Dynamic Archive (DYNA, http://dyna.mi.ingv.it/DYNA-archive/; Figure 1, bottom right panel) is a dynamic database where manually post- processed accelerometric waveforms are provided, together with their metadata. Both of these archives are designed and structured in such a way that their compilations and updat- ing will be almost completely automatic. At the end of May 2012, a first prototype of the ISMD module was published, providing the uncorrected strong- motion data recorded by the INGV stations for the main events of the Emilia seismic sequence [Massa et al. 2012].