Asymmetric picking tools

Asymmetric picking tools

Picking an angular unconformity can be an exercise in frustration. It’s common for automatic propagators to wander off and track down a tilted layer, rather than the depositional surface above.

Insight’s asymmetric horizon picking tools can handle this easily.

DUG Insight’s horizon propagator matches waveforms not events, so a window defines the interval to match. The default window is symmetric, 30ms above and 30ms below the horizon seed point.

To use an asymmetric window, uncheck the box to the right of the Above/Below settings. The Above field unlocks and can be adjusted independently of the Below value.

For this unconformity, we’ve set the Below value to 0 so the propagator only looks at the waveform in the window above the event. Notice Insight does a better job tracking the upper event with the asymmetric window.

Depending on the waveform, you might get even better results by turning OFF (unchecking) the Snap option. In most situations, snapping helps horizon propagation by fine-tuning the resulting pick. With truncated events, however, it can sometimes give worse results. If you’re having trouble, try disabling the option and see how it goes!