Topographic Maps

What they show… Changes in elevation of Earth’s surface Natural features (mountains, lakes, etc.) Man made features (cities, roads, etc.)

Topo Terms… Contour lines – lines on a map that connect points of equal elevation Elevation – height above sea level

Topo Terms (cont’d.)… Contour interval – difference in elevation between 2 adjacent (side-by-side) contour lines Index contours – contour lines that are labeled to help you find the contour interval

Topo Terms (cont’d.)… Map scale – compares distances on the map with distances on the Earth Legend – explains symbols used on the map Benchmark – point of known elevation

Rules to Remember… Contour lines NEVER touch or cross Contour lines make closed circles around hills and depressions for example…

Rules to Remember… Hachure lines are used to show depressions for example….

Rules to Remember… Contour lines form V’s that point to lower elevations when they cross a ridge Contour lines form V’s that point to higher elevations when they cross a stream for example…

Reading a Topo… Determine the contour interval Determine the map scale Identify any hills or depressions Use the legend to identify man made features

Topo Profile… A cross section picture of the land surface Determined by graphing contour lines Shows changes in elevation across a certain portion of the map

Try one…