ContourLine Map Exercise

Acontour interval is the vertical spacing between contour lines. Thelines do not cross each other. The contour interval of the map is 50{(750 – 500) / 5} feet. The bold lines at every fifth contour lineare the index contours [ CITATION Pat02 l 1033 ].

Pointsof elevation in a contour map are calculated from the contourintervals. The elevation point of A is 750 feet, B is 675 feet and Cis 575 feet. The elevation point of A and B is not labeled on thegiven on the contour map given. The elevation is obtained by findinga marked elevation. From the identified contour interval, the numberof contour lines between the point of interest and the marked lineare counted, and multiplied by the contour interval. The productobtained is added to the point of elevation at the identified labeledcontour line [ CITATION Pat02 l 1033 ].

Determinationof the highest elevation involves three steps locating the highestcontour line, determining the point of elevation of the next contourline. The highest possible contour would be the next contour lineless one. The highest lettered location on the map is E, 1000 feet,and the lowest lettered point is C, 575 feet.

Elevationof the highest location on the map is at the Rock Hill, 1000 feetwhile the lowest location on the map is 500 feet.

Thelocal relief is the difference between two points on a contour mapthat are along the same line. The local relief of the landscape is750 – 500 = 250 feet.

Atpoint F, the contour lines are closely spaced compared to point B.This means point F is relatively steeper than point D. Elevationpoint of F is 650 feet and D is 600 feet. Hence, it would be possibleto see point D when standing at point F. Elevation point at B is 650feet and at D is 600 feet. It would be possible to see point D whenstanding at point B.

PointE, 1000 feet is on a ridge crest as demonstrated by the small spacebetween the contour lines.

Theelevation point at C is 575 feet, and that at D is 600 feet. Thedifference is 25 feet. The distance from C to B is 25 * 1,000 =25,000 feet.

RushCreek flows from North to South.

Question15 and 16

Thecircle dotted blue is at the steepest location of the map. The threestreams are drawn bt a red dotted line.

References

Wiegand, Patrick. __Learning and Teaching with Maps__. Washington, D.C. : Psychology Press, 2002.