Topography Maps by jizhen1947


									Reading and Interpreting
   Topographic Maps
Peaks and Valleys

Select a Topic

                 Rules for Drawing Contours

            Tips for Interpreting Contour Patterns

                    Test your Knowledge

                      Link to Topozone
~ Key Terms ~
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
                  Topographic Map
A map that show the elevation of the land, such
  as hills and valleys, using contour lines.
                       Contour Lines

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

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
  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
The closer together
  the contour lines are,
  the steeper the hill is.
  The more spread
  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
When contour lines
 cross a stream or
 river, they form v-
 shaped kinks in the
 lines that always point

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
             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
   a. Valley                  B

   b. Mountain
   c. Plain
• Actually, you would be going uphill. Look at the elevations on the
   contour lines you will be crossing   .
3. In which direction
   does Maple Creek
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
  elevation at the top
  of this hill?
                         C   D
  a. 1240
  b. 1300
  c. 1000

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

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
  a. a mountain
  b. a depression
  c. a valley
           Link to Topozone
The USGS publishes topographic maps of the
  entire country. This website allows you to view
  any of these topographic maps.

Go to this site and use the map search to try to
 locate your city, town, school, or maybe even
 your own house. When you find a familiar area,
 examine the contours to see how well you
 recognize your own topographic features!

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