RULES ofContour Mapping

TOPOGRAPHY• The study of the shapes and features

of the Earth’s surface.

TOPOGRAPHIC MAPS• Map showing 3-dimensional

shape and elevation of land in 2-dimensions

ELEVATION• Height above sea level

• All points on the same contour line have the same elevation.

#1. A contour line represents a single equal elevation.

A

B

DC

Commonly, every 5th line is darker and the elevation shown. This is the index contour.

#2. Where one closed contour line surrounds another,the inner contour line represents the higher elevation .

This is a contour map of a mountain.

#3. Elevation is determined by the contour line interval.

Question:What is the contour line interval here?

#4.Closely spaced contour lines =steep slope.

Widely spaced contour lines =gentle slope.

#5. Where a contour line crosses a stream or river, the contour line bends to form a “V” that points upstream.This is called the Rule of V’s

In what direction is the river flowing?

#6. Depressions are shown using hachure contour lines

The hachures point into the depression. (Hachures = short dashes)

A hachured contour line, lying between two different contour lines, is the same elevation as the lower contour line.

Count up Count down

Contour Elevation Repeats