Maps

Maps A map is a symbolic representation of the surface of a planet There are many different ways this representation can be accomplished Maps vary in the information they carry Maps vary in the way they present that information That is, the same information can be presented in different ways

How to read maps Give this variation, how do you know how to read maps? The legend Example: the representation of elevation, i.e., topography Pictographs (Drawing hills) Hachure = density of hachure represents slope Hypsometry = contour lines Hypsometric tinting = color represents elevation Shaded relief = shadows indicate height of relief

Simply draw in the mountains

Map of Mount Shasta, California 1883

Map of the moon showing hypsometric tinting

Hypsometric tinting with contour lines

USGS Topographic 1:24,000 quadrangle map showing contour lines

Shaded relief compared to traditional contours: Lake Mead

Contour lines Contour lines mark lines of constant elevation. They never cross, but can overlap Closed depressions are often indicated by contours that have tick marks pointing inward Bundles of lines close together indicate steep slopes Few lines far apart indicate relatively flat ground Choice of interval can be difficult if there are both flat and steep areas in the same map The contour interval should appear in the legend Contour interval can be calculated from the labeled contour lines

USGS Map legends

Topographic

Land survey systems

Land Surface Features

Roads and Buildings

Mines, Caves, Lakes