Prospectivity
ree-v0.9
Carbonatite-associated rare earths, Kanye and Molopo
All runs Does not rank
This run does not rank ground
- No competent person has accepted this run yet.
Nothing below is presented as a ranked target. The record stays visible so the next run can be built from what this one found.
Mineral system
REE Rare earths Definition 0.4
Carbonatite-associated rare earths, Kanye and Molopo
Signed by M. Mokgatlhe, MAusIMM CP on 01 Sept 2026
Semi-supervised anomaly detection, carbonatite model · 500 m
Ran 16 Sept 2026, 72 min
Run by: Amini modelling team · Accepted by: M. Mokgatlhe, MAusIMM CP
Capture efficiency
The top 10% of ranked ground holds 48% of the known deposits.
Search-space reduction 94.6%
The share of the modelled area a competent person can set aside for this commodity.
Validation
Blind-site hit rate 67%
Threshold agreed at MS1 50%
Block cross-validation 4 folds, 50 km blocks
AUC 0.68 ± 0.14
Physical constraints
- Prediction requires an alkaline or carbonatite intrusive signature; barren granite is excluded.
- A radiometric thorium high over known sediment is treated as detrital until a source is mapped.
Features and importance
| Feature | Critical process | System role | Importance |
|---|---|---|---|
| Thorium-to-potassium ratio | Source: rare earths travel with thorium in an alkaline melt | Source | |
| Circular magnetic anomaly | Source: the intrusive plug itself | Source | |
| Regolith persistence | Preservation: a weathered cap concentrates the light rare earths | Preservation |
Inputs
| Dataset | Version | Confidence filter | Coverage |
|---|---|---|---|
| Radiometrics, southern tiles | 1997 | C or better, levelled | 40% |
| Regional aeromagnetics | 2004 levelled | B or better | 72% |
| Mineral occurrence register | 2026-07 | C or better | 30% |
Mineral occurrence register covers 30% of the modelled area and is the layer that governs the bounds.
Validation
| Withheld site | Withheld by | Class | In the high class |
|---|---|---|---|
| BS-REE-01 Kanye carbonatite | M. Mokgatlhe, MAusIMM CP | High | In the high class |
| BS-REE-02 Molopo Farms flank | M. Mokgatlhe, MAusIMM CP | Medium | Missed |
| BS-REE-03 Lobatse ring | M. Mokgatlhe, MAusIMM CP | High | In the high class |
Outputs
- Prospectivity surface 0.9 · COG, 500 m
- Confidence surface 0.9 · COG, 500 m
Parameters
- method
- isolation forest, 200 estimators
- classCut
- high ≥ 0.82, medium ≥ 0.60
- labels
- 8 positives, semi-supervised and declared
Limitations and completeness
- Eight positives is a thin label set; the run is an anomaly screen, not a ranked model.
- 1997 radiometrics cover 40% of the area and were flown at 500 m line spacing.
- Awaiting competent-person review: nothing from this run ranks ground until it is signed.
Against the previous edition
This is the first edition of this model.
Targets from this run
1 targets are attributed to this run and are held back from ranking.
| Target | Score | Class | Competent person |
|---|---|---|---|
| GCW-REE-002 Gcwihaba Skarn Corridor | 0.66 | Medium | M. Mokgatlhe, MAusIMM CP |