1. The difference between the two-way travel times of reflected energy detected at two geophone offset distances.
2. (normal moveout, NMO, ΔT) At an offset distance x, the difference in two-way travel time between the detected reflection event at x (tx) and at zero offset (t0), such that ΔT = tx − t0 ≈ x2/(2V2t0), where V is the seismic velocity of the medium above the reflector.
3. (dip moveout, DMO, ΔTd) In the case of a planar dipping reflector, the difference between the moveout up-dip and down-dip, proportional to the angle of dip ɵ, such that: ΔTd = 2χsin ɵ/V, where χ is the offset distance from the mid-point.
"moveout." A Dictionary of Earth Sciences. . Encyclopedia.com. (September 24, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/moveout
"moveout." A Dictionary of Earth Sciences. . Retrieved September 24, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/moveout