Imaging near‐borehole structure using acoustic logging data with pre‐stack F‐K migration

Abstract

We apply a pre‐stack F‐K migration technique to the full‐wave acoustic logging data to obtain an image of geological structures in the near‐borehole region. The data acquisition configuration of acoustic logging, i.e., the span of receivers along the receiver array and a large number of tool positions along the borehole, well suits the requirement for the chosen migration method. The pre‐stack F‐K migration has no dip angle limitation and therefore can handle large angle dips (with respect to the borehole axis) quite well. It can also efficiently handle a large volume of data in one processing. Because it solves the migration problem in the frequency‐wavenumber domain, the F‐K migration can distinguish between up‐dips and down‐dips for a bed boundary intersecting the borehole. The technique has been tested with synthetic and field data sets. A deviated well acoustic logging data set will be used to demonstrate the ability of the technique to obtain clear structural images away from the borehole.