See Also...202 106 ISOM Index Rock and boulders index previous next
revision 05/00
201 Impassable cliff
An impassable cliff, quarry or earth bank (see 106) is shown with a 0.35mm line and downward tags showing its full extent from the top line to the foot. The tags may be omitted if space is short, eg. narrow passages between cliffs (the passage should be drawn with a width of at least 0.3 mm). The tags may extend over an area symbol representing detail immediately below the rock face. When a rock face drops straight into water making it impossible to pass under the cliff along the water's edge, the bank line is omitted or the tags should clearly extend over the bank line.
Colour: black.
Line width 0.35mm (tag 0.12mm)
tag length 0.5mm (minimum), spacing 0.5mm
As ISOM 2000 but tag line width was 0.125mm
Defined as line symbol 201.0, and 201.1 for the tagless symbol.
As this is a line object it can be drawn with any tool. If the bézier tool is used, care must be taken as tag spacing and angle is dependent on location of nodes and handles. See bézier topic for more information.
The default definition specifies a gap between tags of 0.75mm, compared with the ISOM specified distance of 0.6mm. Variation is allowed in the specification, see the Variations in Symbols topic for details.
Unlike the smaller crag symbol (Passable rock face 203), it is not permissible to have an isolated tagless impassable cliff. Use OCAD symbol 201.1, the plain black 0.35mm line, where there is no space for the tags.
A rock slope steeper than 45 degrees.
1) If the cliff has a tight curve or sharp angle the tags tend to overlap. The solution is to cut out the central part of the curve and replace it with a plain black line. Use the default 201.1, impassable cliff.
2) Longer tags are sometimes needed. Use a black 0.12mm line, the distinct cultivation boundary symbol (414) is suitable.
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