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Contours are usuallymaroon, red orbrown.
Contours indicate theshape of the landssurface, i.e.landforms
such as:
Mountains Valleys
Saddles
Plains Gradient or slope is also
indicated by the patternof contours
Contours are lines on Topographic Maps which join areas ofequal
height above sea level (also called altitude or
elevation).
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Contours
Contour interval = 20metres
Verticalscale
Horizontal Scale
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A B
A B
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Horizontal Scale
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A B
A B
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Horizontal Scale
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Horizontal Scale
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Horizontal Scale
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Horizontal Scale
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Verticalsc
ale
Horizontal Scale
S
teeper
Slope
Closerspacingbetween
contours
Gentleslopeorgradient
C o n t o u r s f a r a p a r t
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Horizontal Scale
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A B
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Horizontal Scale
What happens if we keep the Horizontal Scale the same but
stretch the Vertical Scale?
A B
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cale
Horizontal ScaleA B
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Verticalscale
Horizontal Scale
A B
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Ve
rticalSca
le
Horizontal Scale
Vertical Exaggeration
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A B
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87
2. Mark where each contour crosses the line between the two
points
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1. Place a straight edged piece of paper between the two
points
A BA B
3. Mark on the height of each contour and spot elevation40 60 80
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How to draw a cross-sectionow to draw a cross-section
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4. Copy those points onto the base-line of your
cross-section.
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Verticalsc
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87A B
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Verticalsc
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Mark dots on your cross-section at the correct altitudes
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It is likely to drop below the 80m contour here
It will be between 101m and 119m altitude at th
6. Join the dots using a smooth line.
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A B
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This landform is called a saddle
