3-D SYNTHETIC EXAMPLE

Figure  shows a 3-D version of this synthetic. There are 169 receivers in a 13 by 13 grid, the same recording geometry as the SEP passive experiment. The 13 lines are shown in a single plot for convenience. The statics that have been applied are shown in Figure .

The difficulty in handling long-wavelength statics varies dramatically depending on how the local slant stacks are parameterized. In Figure , relatively few local slant stacks were used (a five by five grid spread evenly over the array), with 15 neighboring traces stacked into each. This makes for little overlap between stacks. The statics solution has a large long-wavelength component. In contrast, in Figure , a local slant stack was performed at each receiver, using 5 traces. This results in a greater degree of overlap; most traces contribute to five or six stacks instead of two in the previous case. The solution is less affected by the long wavelength problem, perhaps because of the greater amount of overlap between stacks. The data are shown in Figure  with the better of the two statics solutions applied.

 

syn3d
Figure 9 A 3-D synthetic containing a single dipping event, before (left) and after (right) removal of statics.

 

stat3d Figure 10 Plan view of the 13 by 13 receiver array showing the known statics applied to the synthetic.

 

long3d Figure 11 Statics estimated from relatively few, wide-aperture local slant stacks. This solution has a large long-wavelength component.

 

short3d Figure 12 Using more, smaller stacks with a greater degree of overlap gives a solution closer to the applied statics.

 

app3d
Figure 13 3-D synthetic after application of statics from Figure .