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Erosion gully 109

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Specifications

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.

Colour: brown.

Line width up to 0.25mm

ISOM 1990 Definition

No change

OCAD Methods

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?

Drawing Considerations

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.

Pictorial Descriptions

- BOF Rules, Appendix One

A very narrow re-entrant or ravine, normally dry.

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International Specification for Orienteering Maps produced by the International Orienteering Federation
OCAD produced by Hans Steinegger Software. © 1988-1999 Hans Steinegger. ® OCAD is a registered trademark of Hans Steinegger
This document has been written and coded by Peter Hornsby of Ashby Mapping
Apologies for any mistakes and errors; please inform details of any problems, thanks.
Produced for the Ashby Mapping internet site on 20 November 1997 and 1 December 1999  ©1997-2000 Ashby Mapping
Revised 28 December 1999, 23 March 2000