Legend and geological symbology¶
GeoSection NX generates the section with an automatic legend listing all present layers, grouped by code. You can customise colours, patterns and order.
Automatic generation¶
Each distinct layer present in the boreholes (layer field in CSV / LITH_CODE
in AGS4) generates a legend entry with:
- Layer code (tag, max 8 characters);
- Description (taken from the first occurrence in boreholes);
- Colour auto-assigned (16-colour standard palette);
- Pattern (solid by default);
- Mean thickness computed from the boreholes (informative).
The legend appears to the right of the section in the standard layout, but can be moved below or disabled in Layout → Legend.
Customisation¶
Panel Legend → Edit:
| Field | What it does |
|---|---|
| Colour | Click the swatch → colour picker; or type hex code |
| Pattern | Selection from ISO/UNI standard patterns: dotted (sand), horizontal dashes (clay), small triangles (gravel), wavy (silt), zig-zag (limestone), diamonds (gypsum) |
| Description | Editable (default = first text read from the borehole) |
| Order | Drag to reorder; affects the printed legend |
| Visibility | Checkbox: hide legend entries you don't want (e.g. surface topsoil) |
Manual entries¶
For entries not in the boreholes but you want documented in the legend (e.g. "Hypothetical bedrock"):
- Legend → Add entry.
- Code + description + colour + pattern.
- The entry appears in the legend but does not generate polygons on the section — it stays purely documentary.
ISO/UNI standard symbology¶
Available patterns follow UNI 8842 and ISO 14689:
| Pattern | Typical lithology |
|---|---|
| Dense dots | Sand |
| Sparse dots + dashes | Silty sand |
| Horizontal dashes | Clay / Silty clay |
| Crossed dashes | Silt |
| Small triangles | Gravel |
| Bricks | Stiff clay / Marl |
| Zig-zag | Limestone |
| Diamonds | Gypsum |
| Empty white | Fill / anthropogenic |
| Crosses | Crystalline bedrock (granite, gneiss) |
Patterns are rendered as SVG patterns: they scale correctly in PDF and DXF prints (up to 1:1,000 without pixelation).
Saving the style as a template¶
The legend style is part of the .geosection file: saving the project saves
colours/patterns/order too. To reuse on other projects:
- File → Save As → save a "template" project.
- On new projects: File → Open style template (loads only the legend, no data).
Useful for consultancies that want to standardise the presentation of geological sections across different reports.