Quick Answer: What Is The Shape Of Contour Lines In Case Of A Valley?

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 do we use contour lines?

The purpose of contour lines is to represent the tridimensional shape of the terrestrial surface on a bidimensional map. Contour lines are the intersection of an horizontal plane parallel to the reference level and the topographical surface to describe.

What is a depression contour line?

A closed contour, inside of which the ground or geologic structure is at a lower elevation than that outside, and distinguished on a map from other contour lines by hachures marked on the downslope or downdip side.

What is the space between contour lines called?

Contour lines–usually curved, parallel brown lines–show the shape and elevation of the land by connecting points of equal elevation. … The space between the contour lines is called the contour interval and represents a specific (set) distance.

How do you calculate contour lines?

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 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 basic features of contour lines?

Other characteristics of contour lines are: – Horizontal distance between contour lines is inversely proportional to slope. – Uniform slopes have uniformly spaced lines. – Along plane surfaces, contour lines are straight and parallel. – Contour lines are perpendicular to lines of steepest slopes.

What do U shaped contour lines indicate?

Ridges are represented by “U” or “V” shaped contour lines with their closed end pointing towards lower elevation. U-shaped contours indicate broader ridges, while V-shaped contours represent narrower and sharper ridge lines. Aretes and spurs are often generally referred to as ridges in backcountry recreation.

Why will the contour lines be in irregular shape?

Water flow is perpendicular to contours. The slope between contour lines is assumed to be uniform. The distance between contours indicates the steepness of the slope. Irregular contours signify rough, rugged country.

What are 3 types of contour lines?

There are 3 kinds of contour lines you’ll see on a map: intermediate, index, and supplementary.Index lines are the thickest contour lines and are usually labeled with a number at one point along the line. … Intermediate lines are the thinner, more common, lines between the index lines.More items…

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 are Hachure lines?

Hachures are short lines laid down in a pattern to indicate direction of slope. When it became feasible to map rough terrain in more detail, hachuring developed into an artistic speciality.…

How do contour lines work?

Contour lines are lines drawn on a map connecting points of equal elevation, meaning if you physically followed a contour line, elevation would remain constant. Contour lines show elevation and the shape of the terrain. … In order to keep things simple, topographic maps show lines for certain elevations only.