The effect of the Fresnel zone size on AVO analysis of CMP gathers
Shuang Sun, John C. Bancroft
Reflection energy from a linear reflector comes from an aperture often described by the Fresnel zone. Within the Fresnel zone, the diffraction energy constructively builds the reflection. Energy from the edge of a reflector combines to produce a diffraction that distorts the reflectivity amplitudes. Similarly, reflection energy from a target that is smaller than a Fresnel zone will also have distorted amplitudes that violate the requirements for amplitude versus offset (AVO) analysis.
Diffraction theory is presented to evaluate the reflection amplitudes from small targets and from the edges of reflectors.