# Dictionary:C-wave moveout

With C-wave gathers the moveout will *not* be symmetric (as with split-spread P-wave gathers) and the arrival time expression, for 1D subsurface, is^{[1]}

equation (5.2.5), Thomsen (2002), with the final Taylor expansion term modified by a physically-based denominator designed to enforce proper asymptotic behavior at long offsets.

The non-hyperbolic moveout coefficent tends to be small and may be ignored for large offsets. Nonhyperbolic moveout parameter tends to be positive.

The extra coefficient is defined by

where the anisotropic parameter governs long-offset P-wave moveout.

## References

- ↑ Thomsen, L. (2002), Understanding seismic anisotropy in exploration and exploitation, 2002 Distinguished Instructor Short Course, Distinguished Instructor Series, No. 5, Society of Exploration Geophysicists