On the resolution of statics, structure, and residual normal moveout

The problem of separation of reflection times into the component parts of source static, receiver static, structure time, and residual normal moveout (RNMO) is presented. A new solution is derived which is valid for wavelengths ranging from a group interval at the short end to a distance equal to the separation between the full-fold positions at the long end. In the absence of RNMO, this solution, though not unique, is, however, optimum with regard to stability against noise in general. In the presence of RNMO, the solution is most stable against white noise. Additionally, it is concluded that the underconstrained nature of the problem is of minor practical consequence.The new method is based on the two-dimensional (2-D) spectrum of the reflection times considered as a function of the spatial variables of common depth point (CDP) and offset. The resultant equations yield a simple, explicit solution for each separate wavelength. The computation is rapid and directly controllable by selection of the desired wavelengths.Synthetic examples are used to demonstrate the properties of this method of solution.