Methodology for automated verification and qualification of sidewall core recovery depth using borehole image logs

Abstract

A method of determining the depth of a sidewall core sample taken from a borehole relative to a reference log of the borehole. The method includes obtaining a reference log recorded on a reference log depth scale and a borehole image log recorded on a borehole image log depth scale of a portion of the borehole from which the sidewall core sample has been taken. The method further includes generating a calibrated borehole image log from the borehole image log and the reference log and identifying a candidate sidewall core image artifact in the calibrated borehole image log. The method also includes assigning a confidence value for the candidate sidewall core image artifact based on a characteristic of the candidate sidewall core image artifact, and determining, using the confidence value, a probability that the sidewall core sample was collected at a certain depth on the reference log depth scale.