1. Topography of the Earth
Aim: How is Earth’s topography represented on a map?

2. Objectives: Read topographic maps
Determine elevation and gradients on the map
Create your own topographic map

3. Vocabulary: Topography Contour Lines Contour Interval Slope Gradient
Depression
Altitude
Elevation
River

4. A. Topography is…. The shape of the land
(flat, sloping, hilly, mountainous)

5. B. Some more definitions…
Contour line: A line that connects areas of equal elevation on a map
Contour interval: the difference between one contour line and the next. To find the contour interval, subtract the two values given, and then divide by the number of lines you need to go from one value to the next.
Slope: the angle of the land. The closer the contour lines are on a map, the steeper the slope
Contour Gradient or Elevation Gradient: the rate at which the slope of land changes. The gradient can be either steep or gradual.
Gradient = change in elevation distance

6. B. More definitions continued…
Depression: This symbol is used to show where the elevation goes down, like a hole.
River: a river is usually shown by a wrinkle or bump in the contour lines
Relief: The difference between the highest and lowest point of a fixed area
Landform: geographical feature of an area

7. C. Factors that determine topography:
a. Elevation -the height above sea level (altitude)
b. Relief -the difference in elevation between the highest and lowest parts of an area
c. Landforms - A feature that is formed by processes that shape the Earth (i.e. weathering, erosion, deposition, tectonic plate movements)

8. D. Types of Landforms a. Plain – low flat land, low relief
b. Mountain – high elevation, high relief
c. Plateau – high elevation, low relief

9. Virtual Contour Maps

10. Let’s take a walk up a hill!

11. We’re now at an elevation of 100 meters.

12. Let’s keep going!
100m

13. Now we’re at 200m.
200m
100m

14. Shall we march on?
200m
100m

15. We’ve made it to 300m!
300m
200m
100m

16. On to the peak!
300m
200m
100m

17. We’re on the peak, but what’s our elevation?
300m
200m
100m

18. Let’s add contour lines for every 50 meters and see if that helps.
Any ideas?
Let’s add contour lines for every 50 meters and see if that helps.
300m
200m
100m

19. We know that we are above 350m, but less than 400m.

20. Let’s head down the hill, it’s getting late!
350m
300m
250m
200m
150m
100m
50m

21. Now what’s our elevation?
If you said somewhere between 200m and 250m you are right!
350m
300m
250m
200m
150m
100m
50m

22. Let’s try this again!
350m
300m
250m
200m
150m
100m
50m

23. What’s our elevation now?
If you said 50m or just under, you’re right!
350m
300m
250m
200m
150m
100m
50m

24. Each color change represents a 50 meter increase.

25. Now, let’s try the same hike! Our elevation is 0 meters.

26. Now what is our elevation?

27. If you said more than 150 meters, but less than 200 meters your right!

28. Let’s go a little higher.

29. Think you know our elevation now?
More than 300meters
But less than 350meters

30. If we were standing on the peak, what would be our elevation?
More than 350 meters, less than 400 meters

31. Let’s head down hill.

32. Know our elevation?

33. More than 100 meters,
less than 150 meters

34. Figure 1: Highest elevation = Contour Interval =
Elevation of the outermost line =

35. The contour interval is ___________________
2. Which direction does the river flow? ________________
3. Elevation of points:
A ______ B ______ C ________ D ______ X ______

36. Figure 2… B E C A D