EXAM REVIEW - CONTOUR MAPS ANSWERS

Questions 1 through 6. Refer to Lou-Lulu dialogs and other explanatory material.

7. Refer to Figures 3 and 4. Assume the length of the scale bar is 25 miles, the contour interval is 50 feet, and the elevation of point Q is 728 feet.

 FIGURE 3 FIGURE 4

1. In what general compass direction is the stream flowing?

It is flowing towards the west.

2. What it is the straight-line distance between points R and T?

3. What is the distance along the stream between points R and T?

about 8 to 9 scale bar lengths = 200 to 225 miles.

4. What is the average gradient of the stream between points R and T?

150 feet in about 200 miles = 0.75 ft/mile; 150 feet in 225 miles = 0.67 ft/mile

5. What is the elevation of contour f?

550 feet.

6. What is the difference in elevation between contour d and contour k?

d = 700; k = 800; the difference is 100 feet.

7. What is the azimuth direction going from point R to point Q?

8. Refer to Figure 5 below.

FIGURE 5

Identify locations by use of the grid intersections. For example, point Q is closest to grid intersection K-5 (intersection of red lines).

For each of the following descriptions, choose the location of the best example.

1. The top of a hill located within a depression is located at:

I-9 (intersection of blue lines)

2. The northwest end of a valley located between two parallel ridges is located at:

midway between E-8 and D-8 (intersection of green lines)

9. Refer to Figure 6, below.

1. Which NYC boroughs or parts of boroughs are represented on the map shown in Figure 6? Manhattan and the western Bronx.
2. In general terms, briefly describe the topography.
Manhattan: Manhattan is a narrow, elongated island that trends NE-SW. It is roughly 12 miles long and two miles wide. The northernmost part of the borough is a well-defined, narrow ridge that rises to over 100 feet and occupies the entire width of the island. Further south, a lower, irregular plateau occupies the west-central region. The southermost part of the island is quite low and flat.

Western Bronx: Most of the western Bronx consists of a series of parallel, elongate ridges and valleys that trend NE-SW and rise to over 100 feet. The southern and southeasternmost parts shown are low and flat.

FIGURE 6.