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How do you find the elevation of a contour line?
You can figure out the elevation of any point by finding the nearest labeled line, counting the number of lines above or below it, multiplying by the contour interval, and adding or subtracting the result from the nearest marked contour line. The more closely spaced the contour lines, the steeper the slope.
How is elevation illustrated on a contour map?
Elevations are marked on the index contour lines only. To determine the gradient of elevations, observe the amount of space in between the lines. If the contours are placed close together, then you’re looking at a steep slope.
What is the elevation between contour lines?
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.
How do you read contour intervals?
How To Read Contour Lines
- 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.
- Supplementary lines appear as dotted lines, indicating flatter terrain.
What are the elevations of points C, D and E?
POSSIBLE ELEVATIONS FOR POINTS C, D, AND E: Point C lies between the 540′ and 560′ contours. It must, therefore have an elevation that is more than 540′ and less than 560′. Point D lies inside a 580′ contour. There are no contours nested within that 580′ contour. Since D lies inside a non-hachured contour, it must be higher than that contour.
What is the elevation of an e inside a contour?
Since E lies inside a hachured contour, it must be lower than that contour. The elevation of point E must, therefore, be less than 620′. Because there are no contours nested within the hachured 620′ contour, there is no point inside that contour that has an elevation equal to or less than 620′ minus the contour interval (620′ – 20′ = 600′).
What’s the difference between Point A and B on a contour map?
DIFFERENCE IN ELEVATION: Point A is on the 580′ contour; point B is on the 520′ contour. The difference in elevation is 60 feet. DISTANCE ALONG THE STREAM: On my printed out map, I have marked off the number of inches between B and A. It equals 4.75 inches.
Is the elevation of point D higher than 580′?
Point D lies inside a 580′ contour. There are no contours nested within that 580′ contour. Since D lies inside a non-hachured contour, it must be higher than that contour. The elevation of point D must, therefore, be higher than 580′.