Effect of velocity uncertainty on migrated reflectors

Abstract

SUMMARYWe study the problem of uncertainty quantification for migrated images. A traditional migrated image contains deterministic reconstructions of subsurface structures. However, the input parameters used in migration, such as reflection data and a velocity model, are inherently uncertain. This uncertainty is carried through to the migrated images. We use Bayesian analysis to quantify the uncertainty of migrated structures by constructing a joint statistical distribution of the structures in question. From this distribution we can deduce the uncertainty in absolute positions of the structures, or a relative position of one structure with respect to another. In some cases the relative position has a much smaller uncertainty than the absolute position.