Optimum time-to-depth conversion

Time-to-depth conversion is usually accomplished by converting zero-offset traveltimes, interpreted from a stacked section, to depth using a known velocity field. Time-to-depth conversion is formulated as an iterative procedure producing a depth model which minimizes the differences between zero-offset picked traveltimes and time derived by normal-incidence ray tracing through the model. The input data consist of traveltimes picked from unmigrated stacked sections, as well as assumed interval velocities in each layer. The method can be applied to models with discontinuities such as pinchouts and faults. To illustrate the method, synthetic and field data examples are included. -Authors