Are seismogram recorded in schoola educational tools only ?

Abstract

In the frame of the NERA project and under the WP 8, an inventory of schools hosting seismic stations for educational purposes has been compiled with the aim, among others, to establish a network for data exchange. Such an inventory reveals that there are more than 600 instruments, most of which in full activity, in schools of the Mediterranean area. The number of stations is somewhat proportional to the date when educational projects began (Zollo et al., in press), so countries like France, United Kingdom or Ireland, all places where a long tradition in “seismology in schools” is established , own most of the existing stations. The make and technical characteristics of these devices widely vary: some schools have assembled their own mechanical seismometer with very simple materials while some others have designed an acquisition system and coupled it to a sensor available on the market. In some cases, stations are bought from semi-professional or professional manufacturers that have devoted a special care to the educational field. These factories have designed cheap instruments the technology of which is based on the more expensive instruments that are instead available at professional level. These recording items are often equipped with an internet connection, have a broad-band like seismometer, offer a real time view of the recording (helicorder) and provide data in SAC format. In a sentence, they are very much similar to the devices currently used in professional (national or regional) networks to monitor seismicity. Moreover, in principle stations installed in a country are very much alike or perfectly identical, representing as a matter of fact a semi-professional seismic network.. It is then straightforward to wonder what is the role of the data recorded and stored by these instruments and especially what is the potential of these information. Are these instruments providing any additional information to the professional seismic networks ? Could they complement a professional database ? In this paper a rough analysis of the data collected by a school network is analysed and compared with “official” data. It is shown that in some cases seismograms recorded from stations in schools can perform very well and their data could, under certain circumstances and with some limitations, be used instead of / in addition to professional data.