Topographic Maps Topographic maps cra uel for recreation (hiking, camping), land
ID: 291703 • Letter: T
Question
Topographic Maps Topographic maps cra uel for recreation (hiking, camping), land use planning, and as a base map for geological and watershed studies. Topography is defined as the heights and depths that give the Earth's surface shape. A map is a representation of the Barth, or part of it. The distinctive character- istic of a topographic map is that the shape of the Earth's surface is shown by contour lines. Contours are imaginary lines that join points of equal elevation on the surface of the land above or below a reference surface such as mean sea level. Contours make it possible to measure the height of mountains, depths of the ocean bottom, and steepness of slopes. Vertical aistances above mean sea level (the average of high and low tades),u ferfd s.stanca bdise are called elevations or altitude. Elevations (as feet or meters) are shown Cohtosrn on topographic maps separated by a vertical distance called the contour interval Thinking of contours as shore lines at different sea levels may help in visualiz- ing the three-dimensional nature of topographic contours The choice of an appropria the difference between te contour interval is made largely on the basis of the highest and lowest elevations in the map area- the so-called local relief. In areas of low relief, a closer contour spacing will the most meaningful topographic map patten, commonly ten feet. In mount- adnous high-relief regions, a contour interval of 100 feet may be needed to keep contour lines from becoming too crowded. In the map we use today, the contour interval is 100 feet. While rellef is the difference between the high and low points of an area, scale s the relationship between map distance and ground distance. Map scales aufferent from one map to another. For most Covernment, the scale is 1:24,000 (1 inch In the map we use today, the scale is 1 maps printed by the US ce the map 24,000 inches or 0.38 mi.. a "ratio" scale; a scale such as 1 nh1 mle is a "verbal" inch 1 mile. A scale such as 1:24,000 of the topoge is like a graph with elevation plotted vertically a line, as seen from ground level, is called a maps used for recreation and Real topographic than just contours. The ap include symbols that represent such features may roads, buildings, streams, powerlines, pesent Procedure for Creating a Deronstration Contou Your team has been provided with an opaque Steen and a matching printed ?tour map. Your version of the same contour map, which is We-will add colored water to the tank at indd likemuse annuef observe contour intervals as vertical distan depth-hank so this is somewhat like neasuring the rising green plastic raised relief model it can hold 8o uring a flood.. With the help of an overhiad r level adjathat weter on the model. The map made from the overhead he be the same as the map that goes along with ptojector on the whiteboard wil1 Now answer the following questions:Explanation / Answer
1. Contour interval any of the spaces between vertical lines on a topographic map or globe the difference in elevation such an interval represents. Small contour intervals are used for flat areas, larger intervals are used for mountainous terrain.
2. 100ft
3. Contour lines are used to indicate vertical distances from earth surfaces.
4. 1 inch is 1mile
5. Map scale is used to determine horizontal distance on the earth surface.
6. All contour lines are expressed as vertical intervals above 2500ft.
7. Relief is the distance between high and low points of the area.
8. The elevation of highest contour line on the map is 2900ft.
9. The elevation of lowest contour line on the map is 2500ft. If there were another contour line below that then its elevation would be 2400ft.
10. Approximate relief is 2900-2500=400ft.
11. Elevations of points:
A is 2700ft , B is 2600ft, C is 2500ft, D is 2500ft, E is 2900ft , F is 2800ft, W is 2800ft , X is 2400ft, Y is 2700ft, Z is2500ft.
12. Points B and C horizontal distance is 1 mile relief is 100ft.
Points E and D horizontal distance is 1.3 mile relief is 400ft.
Points Y and X horizontal distance is 10 mile relief is 300ft.
Points W and X horizontal distance is 5 mile relief is 400ft.
Points A and C horizontal distance is 3 inch relief is 200ft.
13. Because streams are found in local topographic lows, the contour lines double back on themselves and forms a "V" shape pattern.
14. Contour lines bend toward north east when they cross Omega river. The water in Omega river flow towards west.
15. The water flow direction in Alpha river is towards south, in Lam creek is towards northeast, in small stream is towards North, in steep creek is towards north, in new river is towards northwest