1. Mapping Earth’s Surface
Topographic Maps
Topographic Map – A map showing the surface features of an area. (They use symbols to portray the land as if you were looking down on it from above.)
Topographic Maps provide highly accurate information on the elevation, relief, and slope of the ground surface.
What uses of a topographic map can you think of? Stores, housing, factories, schools, recreation… ?????

2. Mapping Earth’s Surface
Topographic Maps
Scale: Topographic maps are large-scale maps. This way they can show details of elevation and land features.
Who does this stuff? The agency is called the U.S. Geological Survey (USGS). They do all of the maps for the whole country.
Symbols: Many
different ones
like these…

3. Mapping Earth’s Surface
Topographic Maps
To represent elevation, relief, and slope on a topographic map, mapmakers use contour lines.
A contour line connects points of equal elevation.
The Contour interval is the change in elevation from contour line to contour line. (The space between the lines, and it is always the same on the same map.)

4. Mapping Earth’s Surface Topographic Maps

5. Mapping Earth’s Surface Topographic Maps
Depression – A closed loop with dashes inside indicates a depression.
Hilltop – A contour line that forms a closed loop with no other contour lines inside it indicates a hilltop.
What is the Index Contour of this map?
What is the elevation by the river?
What is missing from this map?
Is GPS listed on this map?

6. Mapping Earth’s Surface Topographic Maps
What kind of information does a topographic map provide about landforms?
How do topographic maps represent elevation and relief?
What would the highest and lowest points in an area look like on a topographic map?
What is the role of satellites in the Global Positioning system?