Topographic Maps: Reading, Contour Lines, and Map Features (module 4)

What is a topographic map?

A two-dimensional representation of three-dimensional space that utilizes contour lines to show elevation.

What do contour lines represent on a topographic map?

Lines of equal elevation.

What does closely spaced contour lines indicate?

Steep slopes.

What does widely spaced contour lines indicate?

Gentle slopes.

What are index contours?

Every 5th contour line that is drawn darker to indicate a change in elevation.

What do contour lines with hachures indicate?

Depressions in the terrain.

What happens to contour lines when they cross?

Contour lines never cross.

What shape do contour lines form when they close?

An irregular circle.

What does a 'v' shape in contour lines indicate?

The direction from which a stream flows.

What is the purpose of contour intervals?

To indicate the vertical change in elevation between contour lines.

How do contour lines appear along a lake?

They run parallel to the lake, indicating ridges and escarpments.

What features can be indicated on a topographic map using USGS symbols?

Marshy areas, strip mining areas, and railroad sidings.

What is the significance of the contour interval in topographic maps?

It determines the vertical distance represented between adjacent contour lines.

What does a topographic map of Mount St. Helens show?

The topography of Mount St. Helens, including its caldera.

What is the role of the US Geological Survey in relation to topographic maps?

They produce and provide access to topographic maps.

What can be inferred from closely spaced contour lines on a site plan?

There are steep slopes in that area.

What does a topographic map reveal about the terrain at Cooper Rock State Park?

It shows areas with steep and gentle slopes based on contour line spacing.