Stereographic imaging condition for wave-equation migration |

Figure 6(h) shows the image obtained by imaging the composite shot, Figure 6(e), using the stereographic imaging condition. The image is free of artifacts and shows reflectors extending over the entire image, as would be expected for illumination from two shots at different locations. In this case, the stereographic imaging condition needs to take into account the local dip of the image. Since we cannot know the reflector dip prior to the application of the imaging condition, we need to loop over a range of possible dip angles and decompose the wavefields locally for all possible slope combinations. Thus, the stereographic imaging procedure matches the dip of wavefield components in local windows around every image point. Assuming that the local geologic dip is known, at least approximately, we could consider looping over a small range of local dips, thus decreasing the cost of the imaging condition. This approach was not used for the examples shown in this paper and remains to be investigated by future research.

Stereographic imaging condition for wave-equation migration |

2013-08-29