Topographic map scales. For usgs topographic maps 124000 is the scale most often used. The best known usgs maps are the 124000 scale topographic maps also known as 75 minute quadrangles. Geomart your expediated source for. Ground area rivers lakes roads distances between features and so on must be shown proportionately smaller than they really are.
A map scale. Selecting the appropriate scale depends on the size of the sheet of paper and the accurate placement of features. The usgs was entrusted with the responsibility for mapping the country in 1879 and has been the primary civilian mapping agency of the united states ever since. Today the usgs has more than 56000 topographic maps of the united states in various scales plus maps of the moon and planets.
Performed at large scales these surveys are called topographical in the old sense of topography showing a variety of elevations and landforms. A larger scale like 165000 means that a map covers a larger area but that it will have less detail. The maps scale tells you how detailed your map is. From approximately 1947 to 1992 more than 55000 75 minute maps were made to.
Map is its scale. Ground area rivers lakes roads distances between features and so on must be shown proportionately smaller than they really are. Topographic maps are based on topographical surveys. Large is small simply defined scale is the relationship between distance on the map and distance on the ground.
A 124000 scale for example means one inch equals 24000 inches in reality. Maps based on metric units use a scale of 125000 where one centimeter equals 025 kilometers.