GeoRas2Vec model – scanned geological map → GIS polygons, faults and unit names
Research preview (v0.6). Code, installation and documentation: GeoRas2Vec on GitHub.
GeoRas2Vec turns a scanned or rasterised geological map into a GeoPackage that opens directly in QGIS or ArcGIS. The GeoPackage holds three things:
- a polygon layer of geological units, with code, name, age and lithology when they can be read;
- a line layer of faults;
- the legend table, with default QGIS styles.
Unit names come only from text printed on the map and from its legend.
This repository holds the model files. The command-line tool downloads them automatically.
Files
| file | role |
|---|---|
best_fp16.pt |
segmentation network (U-Net++ / EfficientNet-B4, RGB + Lab): 10 pixel affinities + fault map |
naming_model.pkl |
scores (text read on the map, polygon) pairs |
legend_ranker.pkl |
ranks the candidate codes of each polygon (text evidence, leader lines, legend swatch) |
prop_model.pkl |
decides when a code read on the map can be propagated to polygons of the same colour |
water_model.pkl |
recognises water / outside-the-map regions |
exemple/ |
example output GeoPackage, legend CSV, QGIS render |
training/ |
training curves and metrics of the network |
The .pkl files are scikit-learn pickles: only load files from this repository.
Usage
git clone https://github.com/PerfectWin7777/georas2vec.git && cd georas2vec
pip install -r requirements.txt
python scripts/vectorize.py my_map.tif my_legend.csv my_map.gpkg
See the GitHub README for the legend CSV format.
Results (never seen during training)
| official test split | large units | small units | map area in the correct polygon |
|---|---|---|---|
| real scans (78 tiles, USGS GMNA 300 dpi) | 94.5 % | 77.0 % | 98.5 % |
| synthetic maps, 4 continents (60 tiles) | 85.2 % | 73.6 % | 90.4 % |
Faults: line-level F1 at 2 px is 0.80 on the real-scan test split and 0.85 on a held-out region.
Names
End to end on a held-out 6144 × 6144 px region of the GMNA north sheet. Polygons and names are both predicted. The ranker and the propagation model were trained without this region.
| area named | names correct | area correctly named | |
|---|---|---|---|
| names from text only | 65.9 % | 94.1 % | 62.0 % |
| + colour propagation | 74.7 % | 93.7 % | 69.9 % |
How it works
Limitations
- A unit whose code is never printed (or never readable) stays Unité non identifiée, with 3 suggestions.
- Sibling units with almost identical colours (e.g.
lK/K) cause most propagation errors. - Real-scan validation is so far on the USGS Geologic Map of North America. The other continents are evaluated on realistic renderings of official vector maps.
- On sea and ice areas the map prints many texts that are not the unit's code: there GeoRas2Vec gives the right code as first suggestion instead of guessing.
- On large maps, unnamed areas can show straight cuts at the 2048 px block edges.
Versions
| version | change |
|---|---|
| v0.6 | English attribute table by default (--lang fr for French), age shown once, fragments < 200 px merged into their neighbours (3× fewer polygons), no colour propagation onto white paper / ice |
| v0.5 | two-scale mutex watershed; fault lines split at junctions; topological contours (no gap, no overlap); water detection; OCR restricted to the legend alphabet; decoding of age prefixes, Ʀ, Є and superscripts; colour propagation over the whole map; block processing of large maps |
| v0.2 | first public release (revision="v0.2") |
The repository was renamed from PerfectWin/geocarto-model to PerfectWin/georas2vec-model (old links redirect).
Citation
Winter Tony, GeoRas2Vec: from scanned geological maps to vector units, faults and names, 2026 – GitHub. Please also cite the data sources listed in the dataset card.