REFERENCES

• Claerbout, J. F., 1992, Anti aliasing: Stanford Expl. Proj. Report, 73, 371-389.

• Gray, S. H., 1992, Frequency-selective design of the Kirchhoff migration operator: Geophysical Prospecting, 40, 565-571.

• Lumley, D. E., and Biondi, B., 1991, Kirchhoff 3-D prestack time migration on the Connection Machine: Stanford Expl. Proj. Report, 72, 123-134.

 

x9-ann
Figure 5 Inline sections sliced from the standard (upper) and anti-aliased (lower) migration volumes, at a constant y=0.225 km. The anti-aliased migration is much more coherent in terms of horizontal structure, a possible salt-sediment interface or two, and shallow faulting above the interpreted salt location, including a slightly clockwise-rotated fault block at 9.5 km and 1.5 seconds.

 

x35-ann
Figure 6 Inline sections sliced from the standard (upper) and anti-aliased (lower) migration volumes, at a constant y=0.875 km. Again, the anti-aliased migration is much more coherent, although of notably lower frequency content. Note the strong salt-sediment interfaces/faults, and the strongly clockwise-rotated fault block at 10.5 km and 1.5 seconds.

 

x92-ann
Figure 7 Inline sections sliced from the standard (upper) and anti-aliased (lower) migration volumes, at a constant y=2.300 km. A salt peak is clearly visible at 8.5 km and 1.5 seconds in the anti-aliased image. This interpretation would be much more challenging given only the standard image in the upper panel.

 

y191-ann
Figure 8 Crossline sections sliced from the standard (left) and anti-aliased (right) migration volumes, at a constant x=7.163 km. Note the coherent resolution of the anticlinal sediment structure in the anti-aliased migration panel. With a little imagination, we might be seeing the top of salt which underlays the sediment package at 2.5 seconds, and the fuzzy bottom of the salt lens intrusion at 3.0 seconds.

 

z16-ann
Figure 9 Time slices cut from each of the standard (upper) and anti-aliased (lower) migration volumes, at a constant $\tau=0.128$ seconds. The anti-aliased time slice shows a continuous 3.0 km long radial fault associated with the salt intrusion.

 

z219-ann
Figure 10 Time slices cut from each of the standard (upper) and anti-aliased (lower) migration volumes, at a constant $\tau=1.752$ seconds. The salt peak has clearly penetrated the anticlinal sediment structure in the lower right corner of the plot. A radial fault (salt-filled?) is barely discernible, but definitely seems to curve into the major discontinuity in folded sediments at $\{x,y\}=\{8.5,1.7\}$ km.

 

z235-ann
Figure 11 Time slices cut from each of the standard (upper) and anti-aliased (lower) migration volumes, at a constant $\tau=1.880$ seconds. Two radial faults are clearly imaged, which bound a fault block containing reflectors that dip steeply and acutely into the plane of the page, especially at x=9.5 km in the y=1.5 km range. In contrast, the anticlinal sediment structure to the left dips more within the horizontal plane of the page.