Welcome to MedNet
Since its initial plan, MedNet was meant to give a contribution to the instrumental coverage of the Mediterranean area with state-of-the-art seismographic equipment. This is indeed a region of high seismicity and a complex tectonic environment. Its interest for earth sciences, and seismology in particular, is high, but high quality, broadband instrumentation is not sufficiently diffused. MEDNET represents an effort to improve this situation.
The project started with this main objective in mind, seeking active cooperation with seismological Institutions in different Countries. Because of the choice of instrumentation -- very-broadband STS1-VBB sensors, and 24 bit Quanterra data loggers -- priority was given to selection of seismically quiet and thermally stable sites. In many areas it was possible to identify, for instance, abandoned mining zones or tunnels in remote regions -- a situation particularly difficult for logistics, which called for instance for power supply on solar systems and did not permit telephone connections.
Data were recorded continuously on magnetic tapes. Even though the contributions of MEDNET data are important for the study of earthquake sources in the region, in the original plan there was no design for rapid data transfer (a limitation imposed by the absence of telephone lines in remote area
Operations started with off-line field data collection. Then dial-up capabilities were gradually added at later stages at selected sites. At present these have been replaced with more efficient TCP connection that allow collecting data in real-time for the whole network.
This important technological upgrade allows a prompt contribution to the seismic monitoring of Italy and of the Euro-Mediterranean Countries since data are exchanced in real-time to other Sismic Networks. Seedlink protocol has been adopted for transmission, in the framework of the European Community MEREDIAN Project (EVR1-2000-40007). As for data archiving and distribution, continuous data streams are collected and stored at the Data Center and are directly available to user requests by the standard NetDC and AutoDRM protocols. Fully automatic functions include now: daily monitoring of state-of-health; triggered retrieval of event waveforms (with magnitude- and region- specific selection criteria), local magnitude determination, and update of web pages for events and station information. Rapid semiautomatic moment tensor solutions are calculated by two different techniques.