A review of the source parameters of the 1999 MS7.6 Chi-Chi, Taiwan, earthquake

An M(s)7.6 Chi-Chi earthquake, which ruptured the Chelungpu fault, struck central Taiwan on 20 September 1999 at 17:47 p.m. GMT. Observed data and inversion results lead to the estimated values of source parameters of the earthquake based on distinct methods for measurement or inversion. In this study, the values of several source parameters, including the surface ruptures, displacements on the fault plane, peak ground velocity (PGV), peak ground acceleration (PGA), predominant frequency (f(o)), corner frequency (f(c)), spectral level (Omega(o)), seismic moment (M-o), static stress drop (Delta sigma(s)), dynamic stress drop (Delta sigma(d)), rupture velocity (V-R), strained energy (Delta E), seismic radiation energy (E-s), etc are reviewed. In addition, the observed source scaling law is also taken into account. Results show remarkable differences in source properties between the northern and southern segments of the Chelungpu fault.