The footsteps of the receiver ghost in the f-k domain

Abstract

Waves traveling upward from subsurface reflective strata continue propagating after they are recorded by receivers as primary reflections. When a sharp velocity discontinuity exists above the receivers, the waves are then reflected back, and are once more recorded by the same receivers but as downgoing waves. This phenomenon is known as the receiver ghost. Based on a thorough study of the f-k response of the receiver ghost in a record, this paper shows that the null frequencies are caused by the time differences between the primary and the ghost arrivals, and that they vary with the angle of incidence. It is further shown that the loci of the null frequencies of each harmonic is a member of a family of hyperbolas with a common pair of asymptotes in the f-k domain.