Station Parameters

Notes on parameters of station-database:

	Country Each country was selected using its recent political boundaries.
	Station Co-ordinates The station co-ordinates have been adopted from bulletins published by the station operators, from the literature or from field observations. All co-ordinates have been carefully checked against maps and the distances to the source or fault to ensure that there are not gross errors. The identified location errors were generally within a few kilometers however we also found station mis-location of up to 90km. The re-examination of all station co-ordinates showed that most of the inaccuracies or errors were due to typographical errors, different geodetic reference systems or units reported in angular degree but published in decimal format or vice versa. Some of the mis-locations were found to be the result of geographical co-ordinates measured on large-scale maps. The latitude and longitude refer to the WGS84 (World Geodetic System 1984).
	Building Type This parameter has been adopted from bulletins published by the station operators, from the literature or from field observations. The building type is classified as "Free-Field", "Structure-Related", "Structure-Related Free-Field", "Arch Dam", "Gravity Dam", "Embankment", "Dam", "Dam-Related Free-Field", "NPP" or "NPP Free-Field".
	Local Site Conditions Local site conditions (local geology and topography, building type, instrument location, etc.) at many European strong-motion stations are poorly known, particularly for the case of old sites that have been moved or abandoned, or for temporary stations. In terms of the soil conditions the majority of sites can only be described at best in very general terms such as "soil" or "rock". There are however some stations for which there is no knowledge of the soil conditions at all. For a small percentage of European stations, relatively detailed descriptions of the local soil conditions do exist. These typically take the form of shear- and compressional-wave velocity profiles, although some are described in terms of standard penetration test, void ratios, density, moisture content and other material property data. For these sites, velocity values can be estimated roughly via empirical relations. In view of the limited data available for many sites, and the intention to uniformly determine values of selected parameters for as many of the records as possible, the scheme proposed by Boore et al. (1993) has been adopted, which uses the measured or estimated average shear-wave travel-time velocity to a depth of 30m (Vs30). The definition "rock" and "alluvium" has been used if it was not possible to classify the local geology according to Boore's scheme: rock Vs30 > 750m/s stiff soil 360m/s s30 £ 750m/s soft soil 180m/s s30 £ 360m/s very soft soil Vs30 £ 180m/s The topographical details at most stations were even less well described. Where they did exist they may be given only in terms of very broad descriptions such as "at the top of a hill" without any reference to the hill dimensions or the surrounding geomorphology. It is not common to have detailed information regarding the structure, in which the instrument is housed, for example building plans, and the specific location of the instrument within the structure beyond (e.g. basement of a 3-story building).
	References Only the most important reference to documents or bulletins has been given from where most of the station-parameters were adopted.