Installation

To cope with the high resolution and dynamic of the sensors and data acquisition, site installation was accomplished with special care. At most sites a cavern was blasted into the bedrock up to 5 meters deep to ensure stable conditions for measurements. The careful selection and remoteness of the sites ensures excellent data quality.

Sites are equipped with Streckeisen STS-2 broadband and Kinemetrics EPI strong-motion seismic sensors connected to a Quanterra Q330/Q330HR digitizer, which samples at a maximum rate of 100 Hz. The magneto-telluric streams are digitized with 20 Hz by an Earth Data Logger (EDL). They are also connected to the SeisComP PC that handles local storage and seedlink communication. Additional data streams collected and transmitted are 1Hz continuous GPS, climatic parameters and web cam pictures of the vault entrance. Stations are self-sufficiently powered with solar panels. Data is transmitted to the GEOFON data centre via a VSAT satellite link.