On strong ground motion synthesis with k-2 slip distributions

This study deals with the methodical aspects of k(-2) (Bernard et al., 1996) kinematic strong motions modelling: (1) it is shown how to incorporate the k-dependent rise time for 2D fault geometry in the strong motion synthesis according to the representation theorem, (2) it is suggested how to produce realistic k(-2) slip models including asperity(ies), (3) modifications are introduced concerning the type of used slip velocity function and the corner wave number in the slip distribution. High frequency effects of these generalized models are discussed. It is shown that, assuming the rise time proportional to the spatial slip wavelength at high wave numbers, the spectral decay of displacement at frequencies higher than the corner frequency is given just by the decay of the slip distribution spectrum, regardless of the type of slip velocity function. It is shown numerically that this model provides omega-squared source spectrum even in a vicinity of a 2D normal fault buried in 1D structure, which is an agreement with previous studies.