Untitled Document. The difference in elevation between successive contour lines on a given map is fixed. This vertical distance between any two contour lines in a map is called
the contour interval (C.I.) of
the map.
What are contour lines that are far apart called?
Contour lines that are relatively close together indicate a slope that is fairly steep. Contour lines that are further apart indicates
a slope that is relatively flat
. The area of the map above boxed in orange shows an area that has a fairly steep slope, while the area boxed in purple is a relatively flat area.
What does the distance between two contour lines on a topographic map represent?
Closely spaced contour lines represent steep slopes, conversely, contour lines that are spaced far apart represent
gentle slopes
.
What is the distance between the two index contour lines what is the contour interval?
Subtract the smaller elevation from the higher elevation. Count the spaces (contour lines) between the two index contours. Divide the elevation difference (step 2)
by the number of spaces
(step 3). That number is your contour interval (distance between contour lines).
What are the 5 Rules of contour lines?
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 two things do contour lines never do?
- Every point on a contour line is of the exact same elevation. …
- By definition, contour lines separate points of higher elevation from points of lower elevation. …
- Contour lines never cross. …
- Contour lines never split.
How do you calculate contour lines?
What Is the Contour Interval Equal To?
Divide the difference in elevation between the index lines by the number of contour lines from one index line to the next
. In the example above, the distance 200 is divided by the number of lines, 5. The contour interval is equal to 200 / 5 = 40, or 40-unit contour intervals.
What is contour lines on topographic map?
The distinctive characteristic of a topographic map is the use of elevation contour lines
to show the shape of the Earth’s surface
. Elevation contours are imaginary lines connecting points having the same elevation on the surface of the land above or below a reference surface, which is usually mean sea level.
What is the elevation difference between contour lines?
The elevation difference between two adjacent contour lines is called
the contour interval (CI)
. Usually the contour interval is noted on the map legend. In most topographic maps every 5th contour line is drawn in bold print or wider than other contours. Such lines are called index contour lines.
What are the methods of contouring?
- Direct Method of Contouring : High degree of precision is required for large-scale maps with small contour interval. …
- Indirect Method of Contouring : It is suitable for undulated ground and hilly areas.
What is meant by 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.
Why can’t contour lines cross?
Contour lines never cross on a topographic map
because each line represents the same elevation level of the land
.
What is major and minor contour lines?
The major contour lines at the decades
are logarithmic values that are equally spaced
, and the minor contour lines are linear values that are logarithmically spaced.
How do you read contour lines on a plan?
Closely spaced contour lines indicate
steep
slope. Widely spaced contour lines indicate gentle slope. Equally spaced contour lines indicate uniform slope. Closed contour lines with higher elevation towards the centre indicate hills.
What are 3 types of contour lines?
Contour lines are of three different kinds. They are
the Index lines, Intermediate lines and the Supplementary lines
.
