IMPLEMENTATION OF THE DEVIATION OPERATOR
, by Ozdogan Yilmaz and Jon F. Claerbout

The deviation operator (Dev) is defined as the error made in separating the double square root operator (DS)
(see Claerbout and Yilmza, this report). A second order approximation to the deviation operator yields an
equation that can easily be implemented. Conventional data processing can be considerably improved by applying
this operator to common offset sections prior to NMO correction. The process tends to correct for dipping
events; thus, together with the NMO, each common offset section is more accurately mapped onto a zero-offset
section. Models of point scatteres at different depths in (a) a constant velocity medium and (b) a medium with
vertically varying velocity were used to test the deviation operator. Results indicate that, following the
application of the deviation operator, the success of imaging common offset sections is comparable to that of
zero-offset sections.