Omega-Squared Model 2
Omega-Squared Model 2 :
A widely used model of earthquake source associated with the far-field body-wave characterized by the displacement amplitude spectrum having the flat low-frequency part and the high-frequency power-law decay (with the power of 2) part separated by the corner frequency. The height of the flat part is proportional to the seismic moment and the corner frequency is inversely proportional to the linear dimension of the source. See Hanks (1979) and Aki and Richards (2002 or 2009, Chapters 10 and 11) for its observational and physical bases. The observed seismic spectra tend to be lower than predicted by this model at frequencies higher than a limit called fmax. A practical procedure for computing the time history of strong ground motion, including the fmax effect, was given by Boore (1983) based on this model
