Horizontal and vertical ground motion prediction equations derived from the Italian Accelerometric Archive (ITACA)

A set of Ground Motion Prediction Equations (GMPEs) for the Italian territory
is proposed, exploiting a new strong-motion data set become available since July 2007
through the Italian Accelerometric Archive (ITACA). The data set is composed by 561
three-component waveforms from 107 earthquakes with moment magnitude in the range
4.0–6.9, occurred in Italy from 1972 to 2007 and recorded by 206 stations at distances up
to 100 km. The functional form used to derive GMPEs in Italy (Sabetta and Pugliese in Bull
Seismol Soc Am 86(2):337–352, 1996) has been modified introducing a quadratic term for
magnitude and a magnitude-dependent geometrical spreading. The coefficients for the prediction
of horizontal and vertical peak ground acceleration, peak ground velocity and 5%
damped acceleration response spectra are evaluated. This paper illustrates the new data set,
the regression analysis and the comparisons with recently derived GMPEs in Europe and in
the Next Generation Attenuation of Ground Motions (NGA) Project.