Quick Answer: What Do The Numbers On Contour Lines Represent?

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 is the space between contour lines called?

The space between the contour lines is called the contour interval and represents a specific (set) distance. If the contour interval is 50 feet, the vertical space between the two contour lines is 50 feet.

What is the importance of 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. Consequently: Contour lines are always closed curves.

What are the five map symbols?

Most maps will have the five following things: a Title, a Legend, a Grid, a Compass Rose to indicate direction, and a Scale. The Title tells you what is being represented on the map (i.e. Austin, Tx).

What are the characteristics of contour lines?

Characteristics of ContoursMust close on themselves, on or off the map.Perpendicular to the direction of max. … Slope between them is assumed uniform.The distance between them indicates the steepness of the slope, gentle or steep.Irregular signify rough, smooth signify gradual slopes.Concentric closed contours: hills or depression.More items…

What is the definition of a contour line?

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. … map: contour lines. The diagram illustrates how contour lines show relief by joining points of equal elevation.

What are the different symbols on a map?

Symbols are small pictures that stand for different features on a map. A symbol is often drawn to look like what it represents. For example, a triangular shape is often used to denote a mountain.

What do the numbers on a topographic map represent?

Contour elevation numbers indicate the direction of elevation by always reading (pointing) uphill. What is scale? Maps are made to scale. In each case, the scale represents the ratio of a distance on the map to the actual distance on the ground.

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.

What is the Colour of contour lines?

The color brown is used to denote most contour lines on a map, which are relief features and elevations. Topographic maps use green to denote vegetation such as woods, while blue is used to denote water features like lakes, swamps, rivers, and drainage.

How do you read a contour line?

How To Read Contour LinesIndex 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. … Supplementary lines appear as dotted lines, indicating flatter terrain.

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.…

What are the 6 basic features of a map?

A good way to remember these features is DOGSTAILS: date, orientation, grid, scale, title, author, index, legend, and sources. Title, date, author, and sources usually appear on the map though not always together.

What are the 5 colors on a map?

Reading Topo Maps: Understanding Map Symbols and ColorsRED -Overprinted on primary and secondary roads to highlight them. … BLACK -Manmade or cultural features.BLUE -Water-related features.BROWN -Contour lines and elevation numbers.GREEN -Vegetation features.WHITE -Sparse or no vegetation. … PURPLE -Denotes revisions that have been made to a map using aerial photos.

What do the colors mean on a topographic map?

The colors of the lines usually indicate similar classes of information: topographic contours (brown); lakes, streams, irrigation ditches, and other hydrographic features (blue); land grids and important roads (red); and other roads and trails, railroads, boundaries, and other cultural features (black).

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.

Why can’t contour lines cross?

Contour lines can never cross one another. Each line represents a separate elevation, and you can’t have two different elevations at the same point.

What are 2 types of maps?

There are two main types of maps – political maps and physical maps. Physical maps show the shape of the land – hills, lakes, forests, the coast and so on. Political maps show how the land is used by people – counties, provinces, countries, town boundaries, etc.

Why do cross contour lines matter?

​A cross-contour drawing uses lines that seem to move along the surface of the objects in the composition. These lines emphasize the volume of the objects by wrapping around them. GOALS: Arrange an interesting, well balanced composition.

What does it mean when contour lines are far apart?

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.