Wave-equation traveltime tomography by global optimization

Abstract:

Wave-equation traveltime tomography is conventionally done by picking the maximum cross-correlation lags between the modeled and observed data. However, a trace-by-trace method of picking makes the velocity update more susceptible to local noise in the correlation as well as inconsistencies in the data. In this paper, I compare the local method of picking the maximum correlation to a global method based on maximizing the stacking power along an interpolated spline surface in the correlation window. The results show that the global scheme is more robust to local noise but sacrifices accuracy and convergence rate.