An updated study on near-fault ground motions of the 1978 Tabas, Iran, earthquake ()

Abstract: This paper presents an updated study and numerical modelling of the Tabas, eastern Iran earthquake (), which occurred on September 16, 1978, using new techniques recently proposed by various researchers. Firstly, the near-fault ground motions recorded at a station very close to the fault were examined based on the characteristics of the velocity pulses and the frequency content of the motions. Evidence of directivity effects in recorded, near-fault ground motion, has been investigated using various methods. In the second part of this paper, stochastic simulations of near-fault, strong ground motion, using finite-fault modelling, based on a dynamic corner frequency recently proposed by Motazedian and Atkinson [Motazedian, D. and Atkinson, G. “Stochastic finite-fault modelling based on a dynamic corner frequency”, Bull. Seismol. Soc. Amer., 95(2), pp. 995–1010 (2005)], have been presented. In order to model the impulsive behaviour of near-fault ground motion, the finite-fault model was combined with the mathematical expression of Mavroeidis and Papageorgiou [Mavroeidis, G.P. and Papageorgiou, A.S. “A mathematical representation of near-fault ground motions”, Bull. Seismol. Soc. Amer., 3, pp. 1099–1131 (2003)] for modelling pulse characteristics. A new set of modelling parameters has been recommended and good agreement has been found between the recorded and simulated response spectra. The velocity pulses observed in near-fault ground motion records could also be mimicked. [Copyright &y& Elsevier]