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This paper describes how the earthquake parameters of historical earthquakes have been determined in Europe from macroseismic data by means of the so-called 'Boxer' method, in the frame of the European Commission 2009-2012 Project SHARE (Seismic Hazard Harmonization in Europe). The problems related to the assessment of magnitude are described with more detail; the methodological issues are developed with special reference to the 'stable continental region'. The paper first describes how the coefficients of the Boxer method are determined in five tectonic regions of the European area from the relevant calibration data sets, and discusses the problems dealt with while performing this task. Then it describes how the results have been checked against data different from those used in the previous phase. Finally, the application of the new coefficients to nearly a thousand of European earthquakes before 1900 is described. Stressing that, for the first time in Europe, homogeneous results have been obtained at such a large scale, the final part of the paper is devoted to analyse such results, with special reference to the general trends and to some case-histories. [ABSTRACT FROM AUTHOR]

We have analyzed the recently developed pan-European strong motion database, RESORCE-2012: spectral parameters, such as stress drop (stress parameter, Δ σ), anelastic attenuation ( Q), near surface attenuation ( κ ) and site amplification have been estimated from observed strong motion recordings. The selected dataset exhibits a bilinear distance-dependent Q model with average κ value 0.0308 s. Strong regional variations in inelastic attenuation were also observed: frequency-independent Q of 1462 and 601 were estimated for Turkish and Italian data respectively. Due to the strong coupling between Q and κ , the regional variations in Q have strong impact on the estimation of near surface attenuation κ . κ was estimated as 0.0457 and 0.0261 s for Turkey and Italy respectively. Furthermore, a detailed analysis of the variability in estimated κ revealed significant within-station variability. The linear site amplification factors were constrained from residual analysis at each station and site-class type. Using the regional Q model and a site-class specific κ , seismic moments ( M ) and source corner frequencies f were estimated from the site corrected empirical Fourier spectra. Δ σ did not exhibit magnitude dependence. The median Δ σ value was obtained as 5.75 and 5.65 MPa from inverted and database magnitudes respectively. A comparison of response spectra from the stochastic model (derived herein) with that from (regional) ground motion prediction equations (GMPEs) suggests that the presented seismological parameters can be used to represent the corresponding seismological attributes of the regional GMPEs in a host-to-target adjustment framework. The analysis presented herein can be considered as an update of that undertaken for the previous Euro-Mediterranean strong motion database presented by Edwards and Fäh (Geophys J Int 194(2):1190-1202, 2013a). [ABSTRACT FROM AUTHOR]