Common-datum-point (CDP) methods
The ray-theoretical concepts as presented in chapter 4 are little tailored to the demands of recording techniques now standard in the seismic reflection method. All ray-theoretical considerations from this chapter on will be put in the context of the common-datum-point (CDP) technique.
The introduction of the CDP method meant a major breakthrough for seismic exploration (Mayne, 1962, 1967). CDP data provide redundancy of information for use in attenuating multiples and random noise as well as for estimating the subsurface velocity distribution. Continuous CDP profiling, now standard practice all over the world, offers numerous advantages over other seismic profiling techniques previously used. In this chapter, we will first review commonly used definitions for the conventional 2-D CDP technique and then extend these to include modern 3-D CDP profiling methods.
Figures & Tables
Interval Velocities from Seismic Reflection Time Measurements
“Over the years, ray theory has furnished the exploration geophysicist with most of the working tools for understanding and interpreting events observed on reflection seismic sections. Even today, notwithstanding the pace at which the more powerful acoustic wave theory is introducing its new tools, ray theory, in the hands of the authors, retains its preeminence for providing insights into fundamental problems in reflection seismology. Professor Krey's earlier contributions are part of ray theory's rich heritage. Alongside C. Hewitt Dix and Hans Durbaum, he elucidated relationships between interval velocity and observed reflection moveout.”