2. Topographic Maps Unit 4.2

3. Types of Maps b b Climate maps give general information about the climate and precipitation of a region. Cartographers use colors to show different climate or precipitation zones. b b Economic or resource maps feature the type of natural resources or economic activity that dominates an area. b b Physical maps illustrate the physical features of an area, such as the mountains, rivers and lakes.

4. Types of Maps…cont. b b Political maps do not show physical features. Instead, they indicate state and national boundaries and capital and major cities. b b Road maps show major roads, airports, railroad tracks, cities and other points of interest in an area. b b Topographic maps include contour lines to show the shape and elevation of an area. Lines that are close together indicate steep terrain, and lines that are far apart indicate flat terrain.

5. Topo map b b Since the 1600s, topographic mapping has become an integral part of a country's cartography. b b These maps (topo maps for short) remain among the most valuable maps for government & the public alike. b b In the United States, the U.S. Geological Survey (USGS) is responsible for topographic mapping.

6. More about topo’s bbTbbThe USGS' primary scale for mapping topographic maps is 1:24,000. This means that one inch on the map equals 24,000 inches on the ground, the equivalent of 2000 feet.

7. How to read a Topo map b When contour lines lie close together they represent a steep slope b When contour lines lie far apart they represent a gradual slope. b b Topographic maps use a wide variety of symbols to represent human and physical features. b b Contour lines are used to represent elevation by connecting points of equal elevation.

8. Looking at Contour Lines

9. A look at some topo maps... A body of water, such as a lake or pond, is drawn to the correct shape and scale of the actual body of water. The entire body of water is blue. The name of the body of water will either be on the blue or nearby. A large river's course is drawn to scale, as is its width, and is entirely in blue. The name of the river will me placed along side the river at regular intervals. If the river is too narrow to depict to scale on the map, then the river is a solid blue line. A HILL is a terrain feature that has low ground on all four sides. It is shown on a map as a series of circular contour lines. The center of the smallest circular contour line is considered the hilltop. The contour lines of a depression make a small circle the shape of the depression, but the difference between a depression and a hilltop is that the small circle of the depression will have small tick marks pointing toward the center of the circle, showing that this is "down" into the depression. Marshy areas are shown as small clumps of blue reeds along with intermittent blue lines. Depending on how much water is present, the marsh symbols may or may not be located in water. Man-made structures are shown as small black square (for most house size structures) or odd-shaped black structures, if a discernable shape can be made on the map. Buildings that are ruins or shells are shown as small hollow squares.