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109 Erosion gully
An erosion gully or trench which is too small to be shown by symbol 106 is shown by a single line. The line width reflects the size of the gully. Minimum depth 1m. The end of the line is pointed.
Line width up to 0.25mm
Defined as line symbol 109.0. Can be drawn with any tool but bézier mode is preferable.
The OCAD symbol is about 0.25mm wide.
Very short gullies do not display or print; keep your gully over 10m long or use two dots of the small gully symbol. Do you really need this detail this small?
See minimum dimensions
The maximum allowed width is 0.25mm which is 3.75m at scale, gullies wider than this should be shown using contours. Too many gully symbols can confuse, extract that part of the map and try drawing using contours, or a mixture using contours for the widest and gullies for the deepest.
- BOF Rules, Appendix One
A very narrow re-entrant or ravine, normally dry.
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