The second problem which can arise involves the completeness of our migration with respect to frequency. The range of needed to cycle through is a function the data spectrum. Figure 3 shows a CMP gather in (,kh) domain. To be correct, our migration must cycle through the top and bottom lines in the plot. However, we must be careful not to cycle too high, as temporal aliasing is still a factor (maximum frequency can be no higher than the Nyquist, ).
spect
Figure 3 A CMP in (,kh) domain. We must cycle equal to or past at the line, but not past temporal Nyquist. |