Imaging Vertical Boundaries Using Duplex Wave Migration

Conventional 3D anisotropic prestack depth migration provides accurate structural boundary information for events with dips from 0 to about 70 degrees. For vertical or near vertical events conventional methods rely on turning wave technology that will only be accurate if the recording aperture is very large and the depth model is known to a very high degree of accuracy. Also, the energy to perform this imaging methodology will only be recorded if the velocity depth model is characterized by significant vertical velocity heterogeneity. Duplex Wave Migration is a newly developed technology that is capable of imaging only vertical events (plus or minus 20 degrees) and it does not require either a large recording aperture or any specific a velocity model that must have strong vertical velocity heterogeneity. It is planned that this paper will provide the first examples of the use of this technology on North African data.