CRG datuming from an irregular datum to a planar datum, upward

To generate a common-receiver gather with the receiver located on an upper planar datum and the shots located on a lower irregular topography, based on the principle of reciprocity, I generate an equivalent common-shot gather with the shot located on the upper planar datum, and the receivers located on the lower irregular topography. The generated common-receiver gather is shown in Figure 15(a). Using the same scheme as that for extrapolating upward the receivers of the common-shot gather, I extrapolate the shots to the upper planar datum. The new common-receiver gather is shown in Figure 15(b). The reflection events have been restored to hyperbolas.

 

CRG110
Figure 15 A common-receiver gather, (a) recorded on an irregular earth surface showing the raw data without any processing, and (b) with the shots upward datumed to a planar datum.