A computer-implemented method includes receiving a plurality of sensor signals, each signal of the plurality of sensor signals being tagged with an associated time and depth. The method also includes selecting a baseline signal. The method further includes comparing a selected sensor signal, of the plurality of sensor signals, to the baseline signal. The method also includes determining a difference between the baseline signal and the selected sensor signal exceeds a threshold. The method includes identifying, based at least in part on the difference, a feature of interest associated with the selected sensor signal.