Migration of seismic diffractions and reflections on corrected record sections or contoured reflection time maps is possible with the most basic of programmable pocket calculators. Such an algorithm using a linear velocity function is given for the Hewlett Packard HP-25 calculator. Adaptation to other scientific calculators of at least 49-step program memories should be easy. Although the mathematics of migration are well understood, programming of pocket calculators requires a formulation involving the fewest possible number of steps. The formulation presented here requires only 6.8 sec to execute. The inputs are a time to the event and a dip in time for the wavefront segment to be migrated. Outputs are the horizontal and vertical coordinates of the migrated point as well as the dip of the reflector. Advantages of the calculator method are many. First, the calculator can be used to determine if and where migration is necessary for a set of data. Only those wavefronts that need migration are migrated. Existing sections can be used without the need for any special processing. One does not need to wait long for the results. Finally, the routine is valid for contour migration of time maps. This is perhaps the best application since one is not restricted to the plane of a single profile.

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