Know that the incident and reflected rays follow different paths, but maintain equal angles of incidence and reflection.
Define and become familiar with the various ways of displaying prestack data such as source gathers, constant offset sections, or CMP gathers in the prestack volume (x, h, t).
Construct a source gather and a constant offset section.
Know that conventional stacking is only valid for horizontal reflectors.
Become aware that care must be taken when forming limited-offset stacks from a range of offsets to create a constant-offset section.
Know that diffractions don’t stack.
A scatterpoint forms a surface in the prestack volume (x, h, t) which is referred to as Cheops pyramid.
Figures & Tables
A Practical Understanding of Pre- and Poststack Migrations: Volume 2 (Prestack)
This volume, SEG Course Notes Series No. 14, is designed to give the practicing geophysicist an understanding of the principles of prestack migration, presented with intuitive reasoning that avoids difficult math. Modeling with common-shot record and a constant-offset section are used to introduce prestack migration. New material in this revised edition of the original 1998 book includes algorithms that lead to and include Claerbout’s inversion method.