In homogeneous media, the presence of anisotropy results in a DMO operator that is 3-D in structure, and often includes triplications Alkhalifah (1997c). Since AMO is a combination of a forward and an inverse DMO, some of the anisotropic DMO operator features will appear in the AMO operator. The combination of anisotropy and vertical inhomogeneity should result in even more complicated AMO operators. The vertical velocity variation considered here is a linear one.