# Topography Maps by jizhen1947

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• pg 1
```									Reading and Interpreting
Topographic Maps
Peaks and Valleys

Select a Topic

Terms
Rules for Drawing Contours

Tips for Interpreting Contour Patterns

~ Key Terms ~
Elevation
A term that describes the height of a point on
Earth’s surface above (or below) sea level.
This point is 6300 feet (1920 meters) above sea
level.

http://www.math.montana.edu/~nmp/materials/ess/mountain_environments/novice/yosemite.jpg
Topographic Map
A map that show the elevation of the land, such
as hills and valleys, using contour lines.

http://www.math.montana.edu/~nmp/materials/ess/mountain_environments/novice/yosemite.jpg
Contour Lines

http://www.topozone.com/map.asp?lat=35.16670759393963&lon=-106.71383553979156&s=25&size=l&symshow=n

Contour lines are lines connecting points of equal elevation. Every point
along the line lies at the same elevation above sea level. Imagine
walking around a hill in such a way that you never go up or down the hill,
but stay at the same level. The trace of your path would be a contour line
of that elevation.
Contour Interval
The vertical distance between one contour line and the next. On any
map, the contour interval must be constant, and must be shown in
the map’s legend. On this map, the contour interval is 20 feet,
because each line represents a 20 foot increase in elevation.
Rules for Successful Contouring
Rule #1

Every point along a
contour line
represents the same
elevation.

This entire line
represents 1200 feet
above sea level.
Rules for Successful Contouring
Rule #2

Contour lines NEVER
split or divide!

Can’t happen!
Rules for Successful Contouring
Rule #3
This is fine!

Contour lines cannot
just stop. They must
either form a closed
loop, or run off the
edge of your map.
?
What’s the elevation
here???
?
Rules for Successful Contouring
Rule #4

Contour lines NEVER,
EVER cross

What’s going on?? Is
this area above or
below 1200 feet?

?
Tip 1: What does contour line spacing
indicate?
The closer together
the contour lines are,
the steeper the hill is.
apart they are, the
gentler the slope.
Traveling along the red
line would be much
steeper than traveling
along the green line.
Tip 2: Which way is the stream
flowing?
When contour lines
cross a stream or
river, they form v-
shaped kinks in the
lines that always point
upstream.

Also remember - Water
always flows
DOWNHILL!                Blue Creek flow towards the East.
Tip 3: Finding the hill tops
Hill tops are easy to find. Just look for the
concentric closed contour lines that form the top
of a hill. Notice the contour lines that form the
two peaks below.
Tip 4: What do those funny
hachure marks mean?
Some features, such as
the Grand Canyon,
lakes, mines, or
sinkholes actually are
holes in the ground.
The hachured
contours indicate a
depression. Don’t
confuse it with a
hilltop!
TOPO QUIZ
Now its time to test your topography map
reading skills. Good Luck!!
1. If you traveled from
point A to point B,
would you be going
uphill or downhill?
2. What landform do
you think this map     A
depicts?                        X
825
a. Valley                  B

b. Mountain
c. Plain
Correct!
Sorry
• Actually, you would be going uphill. Look at the elevations on the
contour lines you will be crossing   .
Sorry
3. In which direction
does Maple Creek
flow?
a. Northeast
b. Southwest
c. Can’t tell from
information given
4. What is the contour
interval of this map?
a. 50
b. 100
c. 400
5. What is the
approximate
elevation at the top
of this hill?
C   D
a. 1240
b. 1300
c. 1000
B

6. Which hike would
be steeper, from A
to B or from C to D?       A

1100
7. What is the contour
interval of this map?
a. 20 feet
b. -20 feet
c. 60 feet

8. What type of
landform is depicted
here?
a. a mountain
b. a depression
c. a valley