Saving and Studying the Seismograms of the Strongest Euro-Mediterranean Earthquakes

Digital preservation of the unique seismological patrimony consisting of historical seismograms and earthquake bulletins, and of related documentation (e.g., observatory log books, station books, etc.), is of utmost importance to avoid deterioration and loss over time (Kanamori, 1988). Dissemination of this seismological material in digital form is of equal importance to allow re-analisys of past earthquakes using modern techniques and the revaluation of seismic hazard.

In 2002 at the ESC held in Genoa, a project entitled "Saving and Studying the Seismograms of the Strongest Euro-Mediterranean Earthquakes" coordinated by Graziano Ferrari (SGA - Storia Geofisica Ambiente) and Nicola Alessandro Pino (Istituto Nazionale di Geofisica e Vulcanologia, INGV) was started. The project has been denominated EuroSeismos (ES) and saw initially the participation of the 24 researchers belonging to 15 countries which then extended to 29 countries from the Euro-Mediterranean area.

The goal of the project was to exploit fully the potential offered by historical seismograms for reappraising historical earthquakes using modern techniques. Necessary steps to pursue the goal above are i.) well organized data-collection, ii.) high resolution digital scanning of the historical material and iii.) dissemination of the digital images, iv) foster the growth of a Euro-Mediterranean community on the topic of the processing of the seismograms of the historical earthquakes.

Because the Sismos facility of INGV (see Michelini et al., 2005, for a recent update on its activities) had already set up a scanning laboratory with dedicated personnel (http://sismos.ingv.it), it was agreed to centralize the image-processing activities and the data dissemination at the INGV headquarters in Rome, where the Sismos facility reside.

By the end of 2005, the project has been capable to gather of the order of 25,000 historical seismograms from a list of 611 earthquakes chosen by the participants. The scanned digital images have been assembled in DVD volumes and mailed to the contributing partners. Similarly, all the historical records are viewable interactively at low resolution and can be requested at very high resolution on the "Seismogram Request" Sismos web site (http://sismos.ingv.it/index2.php?bframe=seismograms.php).

Throughout the four years of the project, financial support has been provided by INGV to SGA which has been in charge of gathering and identifying the relevant material, organizing the material exchange between the participants and INGV, preparing and managing the ES web site, and maintaining the contacts with the project partners. In addition, the project has greatly benefited of the expertise of the Sismos personnel for archiving and managing the large amount of digital raster images.

Finally, in September 2005, it was held in Grottaminarda, Italy, and organized by INGV in collaboration with SGA, the "1st Workshop on the Vectorizazion of Historical Seismograms" in which it was presented and taught how to use it the Teseo2 vectorizer (http://sismos.ingv.it/teseo/, Pintore et al., 2005). About 20 participants from 10 Countries of the Euro-Mediterranean region attended the workshop.

As explained above, the project pays particular attention also to the complementary documentation represented by station bulletins, handwritten station handbook etc. and promotes the recovery, digital scanning and dissemination of these materials.

References

Kanamori, H. (1988). Importance of historical seismograms for geophysical research, in "Historical Seismograms and earthquakes of the world", Ed. W.H.K. Lee, H. Meyers and K. Shimazaki, Academic Press, p. 16-33.

Michelini, A., De Simoni, B., Amato, A., & E. Boschi (2005). Collecting, Digitizing, and Distributing Historical Seismological Data. EOS TRANSACTIONS AGU, 12 July 2005, Vol.86, No.28.

Pintore, S., Quintiliani, M. Franceschi, D. (2005). Teseo: A vectoriser of historical seismograms, Computers & Geosciences 31, p. 12771285.