PAD-1.0 Portuguese Accelerometer Database, CD-ROM Edition

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Mainland Portugal, located in the vicinity of the Azores-Gibraltar plate boundary, is exposed to large magnitude ( M 8.0–8.5) distant interplate earthquakes and moderate magnitude ( M 7.0) local intraplate earthquakes. Such events, although infrequent, are relevant in terms of seismic hazard assessment and risk management, in particular in the Lisbon metropolitan area and the Algarve region (Vilanova and Fonseca 2007). The Azores archipelago, located at the North America, Eurasia, and Africa triple junction, is the source location of frequent low-magnitude events and seismic swarms and occasional moderate ( M 7.0) magnitude earthquakes. Figure 2(C) shows the general tectonic setting of the above-cited regions. Under the framework of the European Commission Project NERIES (Network of Research Infrastructures for European Seismology), the Portuguese accelerometer database PAD-1.0 was organized in a MySQL server and compiled in a CD-ROM edition. For each waveform, PAD-1.0 includes relevant information on the earthquake parameters, recording stations, and recording instruments, and a simple query interface allows users to select data that fulfills specific requirements. The search interface and the data request follow very closely the format implemented at the Internet site for the European Strong-motion Database (http://www.isesd.cv.ic.ac.uk/; Ambraseys et al. 2002). The publication of ground-motion data is generally recognized as an important step toward understanding ground-motion properties worldwide ( e.g. , Theodulidis et al. 2004). This work represents a first effort toward the organization and dissemination of the Portuguese accelerometer database. The first strong-motion instruments installed in Portugal were a Japanese SMAC accelerograph on the north pier of Lisbon “25 de Abril” bridge and a SMA-1 Kinemetrics accelerograph at Pico Island (Azores) during the 1960s. These analog instruments provided records on photographic paper for the 1969 MS 8.0 St. Vincent earthquake, the 1973 Pico Island crisis, and the 1980 M 6.9 Terceira Island earthquake. The currently operating accelerometer …