The CDR Method: Chapter 2 of a Thesis in Progress
, by Chuck Sword
The method of Controlled Directional Reception, developed over the last several decades in the Soviet Union, is based on picking traveltimes and ray parameters from short-base slant stacks. The slant stacks can be carried out over common-shot and common-geophone gathers, or over common-midpoint and common-offset gathers. Once the parameters have been picked, they can be used in imaging and velocity analysis. Imaging methods include time migration and depth migration. In addition,
each set of picked parameters contains enough information to determine
an average velocity, and with some care, this velocity can be used in
the imaging.
Stereo pairs can be formed, with velocity as the third dimension.