Map Accuracy Standards - USGS

← Back to document page

Map Accuracy Standards As applied to the USGS positions from aerial photographs. Field Map Accuracy quadrangle topographic map, the hori- survey methods are the only tests An inaccurate map is not a reliable map. zontal Accuracy standard requires that the accepted for official Accuracy testing. X may mark the spot where the trea- positions of 90 percent of all points Positions must be obtained by surveys of sure is buried, but unless the seeker can tested must be accurate within 1/50th of a higher Accuracy . Vertical tests are run locate X in relation to known land- an inch ( centimeters) on the map.

accuracy standards and carry the state-ment, “This map complies with National Map Accuracy Standards.” Exceptions to this practice involve areas covered by dense woodland or obscured by fog or clouds; in those areas, aerial photographs cannot provide the detail needed for precise mapping. The USGStests enough of its maps to ensure that the ...

  Standards, Accuracy, Accuracy standards