Predictions and interpolation
Estimate values between measured samples, then compare the result with the original drilling and geological context.
What a prediction represents
A prediction is an estimate based on the input data and the interpolation method you choose. A block model represents estimated values in cells; a surface represents a selected boundary or threshold.
Use these outputs to explore interpretations and compare scenarios. They are not additional observations. Inspect the drilling coverage, gaps, and source data before relying on detail between holes.
Create a prediction from a 3D scene
- Open a 3D scene containing the intended drilling.
- Open Prediction Models from the prediction controls and select New Prediction.
- Choose an available target: assays or lithology. For assays, confirm the element and measurement method.
- Choose a supported method and output type, then review the input and resolution settings.
- Submit the run and follow its progress in Ongoing Predictions. Open completed results from Past Predictions.
Choose a supported method
| Method | How to think about it |
|---|---|
| Inverse Distance Weighting | Nearby samples contribute more strongly than distant samples. Available for assay targets. |
| Nearest Neighbors | Uses nearby observations for a local estimate. Available for supported assay and lithology targets. |
| Kriging | Uses a geostatistical model of spatial variation. Review the variogram and neighborhood settings. |
| Structural Grade Envelopes | Builds bounded grade shells around supporting intercepts. Review grade thresholds, supporting holes, reaches, and surface resolution. |
The dialog shows settings for the selected target and method. Start with a comparison you can evaluate against known geology, then vary one important setting at a time.
Check the settings that affect interpretation
- Grade cap: clamps input grades above the selected value. It is different from the grade threshold used to draw a shell.
- Treat unspecified intervals as zero: fills uncovered drillhole intervals with zero for the selected element when enabled. Review whether that assumption suits your data.
- Block size or surface resolution: controls output detail and computational effort. Smaller cells do not create new geological evidence.
- Neighbourhood, support, and reach: control how far observations influence the result.
- Output type: choose surfaces or a block model when the target and method provide that option.
Settings differ by method. Structural Grade Envelopes include their own treatment of bounding intervals; read the description shown with the selected mode before running it.
Compare the completed result with drilling
Open a completed run from Past Predictions and check its target, method, date, and parameters. Keep the source holes visible, compare several views, and inspect the areas where the result extends furthest from observations.
For surface point datasets, a separate interpolation workflow is available from supported map layers. See Maps and survey layers.