An empirical spectral ground-motion model for Iran

A new ground-motion prediction equation for 5%-damped horizontal spectral acceleration applicable to Iran is presented. On the basis of analysis of variance (ANOVA), selected West-Eurasian records are added to an existing dataset of Iranian accelerometric data to yield a ground-motion prediction equation applicable at wider ranges of magnitude and distance. The advantages of using this model rather than those proposed previously for Iran are discussed by considering the distribution of residuals against the explanatory variables, magnitude and distance. The applicability of the proposed model, as well as those of several other models developed for shallow crustal environments, is also investigated by means of statistical tools. The results reveal the overall suitability of the new model as well as the validity of models developed using mainly Eurasian strong-motion records.