  In this paper, a new earthquake location method based on the waveform
inversion is proposed. As is known to all, the waveform misfit function is very
sensitive to the phase shift between the synthetic waveform signal and the real
waveform signal. Thus, the convergence domain of the conventional waveform
based earthquake location methods is very small. In present study, by
introducing and solving a simple sub-optimization problem, we greatly expand
the convergence domain of the waveform based earthquake location method.
According to a large number of numerical experiments, the new method expands
the range of convergence by several tens of times. This allows us to locate the
earthquake accurately even from some relatively bad initial values.
