What are contour lines on a map definition?
contour line, a line on a map representing an imaginary line on the land surface, all points of which are at the same elevation above a datum plane, usually mean sea level. Numbers on the lines give the height in feet. (Sea level is zero.) Lines drawn closely together indicate that a slope is steep.
What are the 3 types of contour maps?
There are 3 kinds of contour lines you’ll see on a map: intermediate, index, and supplementary.
What is a contour loop?
Concentric circles indicate a hill. When contour lines form closed loops all together in the same area, this is a hill. The smallest loops are the higher elevations and the larger loops are downhill.
What are the 3 rules for contour maps?
Rule 1 – every point of a contour line has the same elevation. Rule 2 – contour lines separate uphill from downhill. Rule 3 – contour lines do not touch or cross each other except at a cliff. Rule 4 – every 5th contour line is darker in color.
What is the contour interval of the map?
A contour interval is a vertical distance or difference in elevation between contour lines. Index contours are bold or thicker lines that appear at every fifth contour line. A contour interval in the survey is the vertical distance or the difference in elevation between the two contour lines on a topographic map.
What is an example of a contour line?
In cartography, a contour line (often just called a “contour”) joins points of equal elevation (height) above a given level, such as mean sea level. A contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.
What are the four types of contour line?
There are several different contour lines used in art; they include: continuous contour, blind contour, partially blind contour, and cross contour.
What is the contour interval?
A contour interval is the vertical distance or difference in elevation between contour lines. Index contours are bold or thicker lines that appear at every fifth contour line. If the numbers associated with specific contour lines are increasing, the elevation of the terrain is also increasing.
What are the 8 rules of contouring?
|General Rules for Contour Lines|
|1.||Contour lines connect points of equal elevation; therefore every point along a contour line is the exact same elevation.|
|3.||Contour lines never split or divide.|
|4.||Contour lines always separate points of higher elevation (uphill) from lower elevation (downhill).|
What do you mean by contour interval?
What are the different types of contour lines on a map?
There are 3 kinds of contour lines you’ll see on a map: intermediate, index, and supplementary. 1. Index lines are the thickest contour lines and are usually labeled with a number at one point along the line. This tells you the elevation above sea level. 2. Intermediate lines are the thinner, more common, lines between the index lines.
How do I determine the elevation of a contour line?
To determine their elevation, you’ll need to know the contour intervals. Contour intervals tell you the change in elevation between any two contour lines. You can find the contour interval in the map key, usually located underneath the scale of the map at the bottom center. To understand all map symbols, see the US Gov document.
Why are the contour lines in this figure equally spaced?
The contour lines in this figure are equally spaced. The even spacing indicates the hill has a uniform slope. From the contour map, a profile can be drawn of the terrain. Example 2 – Draw a profile showing the elevations of the contours.
How do I find the contour interval on a map?
You can find the contour interval in the map key, usually located underneath the scale of the map at the bottom center. To understand all map symbols, see the US Gov document. Example: The contour interval is 50 feet according to the map key.