Table 3.

Global parameter estimates for each of the four simulations of wave propagation in homogeneous ITI material. Mainly fast shear waves are excited in simulation 1 (see Figure 2b). A mix of slow and fast shear waves are excited in simulation 2 (see Figure 2c). Slow and fast shear waves are excited equally in simulations 3 and 4 which are shown in Figure 2e and Figure 2f, respectively. The material parameters used for all four simulations are μ = 1000 Pa, ϕ = 1, ζ = 2, and η = 0.2. The filter directions in Figure 2g are implemented in both DFI methods. Since the DFI-LFE method is not able to estimate the loss factor η, no estimate is given in the table.

Method	Simulation	μ	ϕ	ζ	η
DFI-LFE	1	2520	0.05	−0.07	-
	2	1290	0.12	−0.06	-
	3	981	0.62	1.79	-
	4	981	0.62	1.79	-
DFI-LDI	1	2760	−0.03	−0.04	0.15
	2	1390	0.07	−0.07	0.21
	3	1050	0.67	1.20	0.17
	4	1050	0.67	1.20	0.17
Curl	1	188	−0.18	14.6	0.28
	2	1000	0.87	1.29	0.26
	3	1010	0.93	0.86	0.17
	4	1010	0.93	0.86	0.17