Wellbore path-matching demo
A horizontal well has to stay inside a thin rock layer. Past the point where depth measurements stop, this model predicts where the layer is by matching the drill bit's gamma-ray readings against a reference well. It runs right here in your browser: change the settings and it reruns on all ~7,000 points of the well.
Path matching error
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RMSE on the predicted section
Baseline error
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Regional plane only
Error vs. baseline
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Rock layer relative to the regional baseline
- Actual
- Path matching
- Baseline
- Known data
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Line chart of the rock layer's depth offset from the regional baseline along the well, comparing the actual layer, the path-matching prediction and the baseline.
Show as a table
| Measured depth (ft) | Actual (ft) | Path matching (ft) | Error (ft) |
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What you're looking at
- Baseline: fit a tilted plane through the target rock layer in nearby wells, then anchor it using the known part of this well. In this demo each well's plane comes only from the other two sample wells, so nothing leaks from the answer.
- Path matching: at every foot past the known section, try every depth offset in the search window, score how well the gamma-ray reading matches the reference well at that depth, and penalize sudden jumps. The Viterbi algorithm then finds the single best path through all of them.
- Try: shrink the known data to 10% and see how far the prediction holds up, or set smoothness to the minimum and watch the path start chasing noise.
Data: the three public sample wells from the ROGII Kaggle competition. Read the case study or the code.