Effects of Parameterization in Acoustic Laplace-domain Waveform Inversions

We examined the effects of slowness, sloth, and bulk modulus parameterizations instead of the conventional velocity parameterization for full waveform inversion in the Laplace domain. Introducing the slowness, sloth, and bulk modulus has an effect of preconditioning the gradient direction of the velocity parameterization due to the chain rule. We compared effects of different parameterization methods in acoustic Laplace-domain inversions using the l-BFGS method. Inversion results using the Pluto model and the SEG/EAGE salt model show that the slowness parameterization yields the best convergence characteristics and final results among those from the four different parameterization methods.