Topographic Maps GEOSCI/ENVIRON 118 Laboratory

Transcription

1 GEOSCI/ENVIRON 118, Laboratory 2 Topographic Maps, page 1 Topographic Maps GEOSCI/ENVIRON 118 Laboratory Name: Section: This laboratory will introduce you to the basic features of maps, including methods for describing locations and land areas, understanding map scales and symbols, and interpreting contour lines to show the third dimension (vertical) of a land surface. Specific concepts that will be introduced or reinforced include the quadrangle map, contour lines, latitude and longitude, scale (fractional, graphic, and verbal), magnetic declination, and azimuth. Task I. On the figure below three streams are represented as thin, dashed lines. Elevation points (black dots with elevations shown in meters) have been surveyed along stream courses and along stream divides. The 800-meter contour line (thick, black line) has already been drawn. Draw all other contours, applying a 20-meter contour interval. Make sure to label each contour line with its label at selected, strategic spots.

2 GEOSCI/ENVIRON 118, Laboratory 2 Topographic Maps, page 2 Task II. Construct a topographic profile along line X-Y on the map below. To do this, first fill in missing elevation values for contours on the map (notice that the contour interval is 100 meters). Then, take a separate piece of paper and place the edge along the X-Y line. Mark the location and elevation of X, Y, and each contour line along the edge of the paper. Transfer the information from the paper to the profile grid by plotting a point of elevation at every instance that a contour line crosses the profile line. Finally, connect the points to complete your profile, remembering to pay attention to whether the elevation increases or decreases between elevations of the same value. (Note that the vertical scale on the profile goes up to 700 m. What this represents in terms of a fractional scale depends on the way the figures are printed, but something like the vertical scale being twice the horizontal scale is not unreasonable. The relief is exaggerated, a common circumstance designed to enhance the visual character of a topographic profile.)

3 GEOSCI/ENVIRON 118, Laboratory 2 Topographic Maps, page 3 Task III Use the map provided to answer the following questions. Show your work for all mathematical problems. 1. What is the name of this quadrangle? 2. What year was this map published? 3. What is the name of the quadrangle to the east of the area shown in this map? to the southwest? to the north? 4. What is the latitude of the southern boundary? 5. What is the latitude of the northern boundary? 6. What is the longitude of the eastern boundary? 7. What is the longitude of the western boundary? 8. What is the size of the quadrangle in angular units (that is, how many degrees and minutes of area does it cover)? 9. Locate the Gravel School Building. Define its location in terms of latitude and longitude, to the nearest minute.

4 GEOSCI/ENVIRON 118, Laboratory 2 Topographic Maps, page Define the location of the Gravel School Building in terms of UTM coordinates, to the nearest 100 m. If you need a refresher on what UTM is, go to What is the fractional scale of this map? 12. Use the graphic scale to determine the distance in miles and kilometers between the Gravel School Building and the C. Pouch School Building. 13. What is the approximate verbal scale for this map in terms of inches and miles? 14. If you wanted to enlarge part of the map to a scale of 1 inch to 1000 feet, by what factor would it have to be enlarged? Explain your answer. What would the enlargement factor be if you wanted a scale of 1 cm to 100 m? 15. What magnetic declination (in degrees) is indicated on the map, and for what year? 16. What is the contour interval for this map?

5 GEOSCI/ENVIRON 118, Laboratory 2 Topographic Maps, page What is the highest elevation within the area designated by your instructor? What is the lowest elevation in that area? What is the relief in that area? What is the height of the feature designated by your instructor in the same area? 18. Find the C. Pouch School Building again and give its elevation. 19. In what direction does the water flow in the Grand River? 20. Find the road from Napoleon (in the northeast) to Jackson. The road runs rather straight from Napoleon to Eldred Schools. (A) What is the direction of travel expressed as an azimuth of a vehicle proceeding towards Jackson on this road segment? (B) What is the direction of travel expressed as an azimuth of a vehicle proceeding towards Napoleon on the same road segment?