Contour Interval On A Map

On most maps determining contour interval is easy just look in the margin of the map and find where the contour interval is printed ie. The contour interval is an even space that represents an increase in elevation.

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Ive been playing around with some maps that use contour lines as an intermediate step in deriving the final style while not necessarily appearing on the map themselves.

Contour interval on a map. Contour interval 20 ft. A maps legend usually identifies the contour interval on the map but sometimes only part of a map is available. Considering the size of the area to be mapped contour intervals are assumed.

As noted earlier an index contour is one that is a bolder darker contour line. 124 000 contour map of many tens of square kilometers or miles might have a contour interval of 40 m. The contour interval measurement given in the marginal information is the vertical distance between adjacent contour lines.

The space between contour lines on a topographical map is a contour interval. This reference line is an index contour. One example is an attempt at hachures.

To determine the elevation of a point you must have a reference line from which to start. The contour interval in a topographical map is the amount between one circle and the one inside of it. For example a course or large scale eg.

Contour lines serve as starting points. For example if there was a circle and another one outside of it but the amount inside is thin. To determine the elevation of a point on the map a.

But the stylistic possibilities with contour lines dont need to stop at contours themselves. When topographic maps are generated and contours created the spacing between neighboring contour lines is defined as the contour interval. A contour interval in surveying is the vertical distance or the difference in the elevation between the two contour lines in a topographical map.

The gradient of the function is always perpendicular to the contour lines. When the lines are close. For instance if the map uses a 20 foot interval there are contour lines at zero 20 40 60 80 and 100 feet.

Before the elevation of any point on the map can be determined the user must know the contour interval for the map he is using. Knowing how to calculate the contour interval becomes a useful skill. More generally a contour line for a function of two variables is a curve connecting points where the function has the same particular value.

The contour interval of a contour map is the difference in elevation between successive contour lines. Usually there are different contour intervals for the different maps. For the maps on this web site however the contour interval is not listed because we only have parts of topographic maps not the whole map which would include the margin notes.

Before you ever start analyzing contours you should determine the contour interval which is found in the bottom center of the map. On most maps every fifth contour line shown as a heavier or darker line is an index line or index contour.

Determine Contour Interval And Contour Line Values