New Developments Of The Geoscope Program

The GEOSCOPE observatory consists of a global seismic network and a data center. The observatory was launched in 1982 by the French National Center of Scientific Research (CNRS/INSU) and progressively 30 stations have been installed across all continents and on islands throughout the oceans. The GEOSCOPE stations are located on 18 countries and equipped with three component very broadband seismometers (STS1 or STS2) and 24 or 26 bit digitizers, as required by the Federation of Seismic Digital Network (FDSN). In most stations, a pressure gauge and a thermometer are also installed. In 2008, 17 stations send data in real or near real time to GEOSCOPE Data Center. In 2008, two stations have been upgraded and send real time data: UNM in Mexico and HDC in Costa Rica. Two new stations have also been installed: CLF in France and FOMA south of Madagascar. In 2009, we plan to upgrade stations PPT in French Polynesia, COYC in Chile, MPG in Guyana and to install a new station in Rodrigues island. We also plan to progressively replace original STS1 electronics with Metrozet systems. In the same time, we will reinstall all STS1 with warpless base plate systems in order to minimize the effects of atmospheric pressure variations thus to improve signal noise ratio. Continuous data of all stations are collected in real time or with a delay by the GEOSCOPE Data Center in Paris where they are validated, stored and made accessible to the international scientific community. Users have free and open access to: - Real time data coming from 17 stations to Geoscope Data Center using the seedlink protocol developed by GEOFON (GFZ, Germany). Seedlink also enables to make these data accessible in real time to Tsunami Warning Centers and to other data centers. These data are also available to users through the GEOSCOPE web interface. - Validated continuous waveforms and meta data of all stations by using the NetDC system (Networked Data Centers). Data can be requested from GEOSCOPE Data Center and from other networked centers associated to the FDSN. - A selection of seismograms corresponding to large earthquakes via a web interface - The power spectrum estimates of the seismic noise averaged over sequences of 24 hours for each station. The noise level of the last 10 years of continuous data has been computed and is accessible via the web. The noise level of real time data is computed at day-8. GEOSCOPE data center is now networked to the French virtual data center, FOSFORE, in order to give a unique access to French seismological data. In Europe, GEOSCOPE data center participates in NERIES project (NA3 activity) in order to create a distributed archive and database for all continuous digital waveform recordings of the Euro-Med region.