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TOPOGRAPHIC PROFILES

A topographic profile is a vertical ‘slice’ through the landscape constructed
along a straight line of profile drawn across a topographic map. A topographic
profile shows changes in relief (change in elevation) in the vertical dimension as a
silhouette. We construct topographic profiles to get a ground-level view of the lay
of the land (Figure 4.8).

Topographic Profile
(ft.) 300 SE Bald Mt. NW

Elevation 200 Little Round Top Red River
250
150
100
Horizontal Scale 1:1800 Datum is Sea Level

Fig. 4.8 Example of a topographic profile

A well-constructed topographic profile must also include the following
information:

• A description of the line of profile, including the name of the map quadrangle
from which the profile was derived and the compass directions at each end of
the profile (i.e., SE and NW).

• Above the profile, letter in the names of prominent geographic features, such
as rivers or mountains. The space below the profile line may be needed for
showing geologic structure. Therefore, even though the profile line is
intended to show the configuration of the land surface only, form the habit of
keeping clear the space below the profile line.

• All profiles should be labeled with a horizontal scale (taken from the map),
vertical scale (determined by the maker of the profile), a vertical exaggeration
(see explanation to follow), and the datum used to control the vertical scale
(usually sea level).

INSTRUCTIONS FOR DRAWING A TOPOGRAPHIC PROFILE

A. Select the line of profile on the map (figure 4.9).

B. Place the edge of a blank strip of scrap paper along the line of profile. You
may want to tape down the ends of this strip of paper so it will not move
while you are working with it.
Using a sharp pencil point, make precise tick marks at places where

contours and other features on the map (streams, tops of hills, etc.)
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