Landslide force history inverted from long-period seismic records for a
landslide has been used to extract its physical parameters. An important
precondition is that the inverted landslide force histories are
reasonable approximations. We first discuss how to estimate the accuracy
of the inverted force histories and then propose an approach to
determine the proper frequency band used in the inversion. We perform a
long-period seismic waveform inversion for the 2003 Qianjiangping
landslide to obtain its force-time history and estimate its movement
parameters. Based on the results, we build a simple model to study the
effects of the portion of the initial sliding mass and the location of
the mass entrainment on the seismically estimated mass, which shows that
if the entrainment occurs at the slow-down phase the seismically
estimated mass is a closer approximation of the initial sliding mass.