GEOL 385- Geomorphology
Spring, 2007
Laboratory 1: Topographic Maps
Instructions: You make work alone or in pairs. Ultimately, each individual must turn in
his/her own copy of this assignment for a grade. Please refer to your GEOL 110 lab
manuals for a review of topographic maps, if needed. Note: there are 2 different
Bridgewater Maps.
1. What is the name of this map? Bridgewater Quadrangle
2. How many minutes of latitude and longitude does this map cover? 7.5
3. Give the coordinates (lat, long) of the center of the map.
38 degrees 26 minutes 15 seconds latitude
78 degrees 56 minutes 15 seconds longitude
4a. What is the latitude and longitude of Mole Hill (in degrees, minutes seconds)?
W-38 degrees 27 minutes 25 seconds latitude
N- 78 degrees 57 minutes 25 seconds longitude
4b. Using UTM coordinates, what is the latitude and longitude of Mole Hill?
W-57,250 latitude
N- 78,750 longitude
5. How would the area covered by a 7.5 minute map in Alaska compare to the area of
this quadrangle? Why? Same
6. What do the following colors represent?
Green
Red
Black
Blue
Brown
White
Purple (if present)
7. What are the contour interval and the index contour interval of this map? Same
8. What year was this map first published? When was it last edited?
Either 1964 then revised in 1987 or 1989 with no revisions.
9. What quadrangle is located to the southwest of this map? If the information is not
present how would you go about finding it?
Briery Branch
10. What is the respective ratio scale of this map? Same
11. What is the verbal scale, or unit equivalents, of this map (x inches on the map = x
feet in the real world). Same
12. What geographic direction does Linville Creek flow (upper right quadrant)? Why
is it represented in a discontinuous line?
South to North- Karst topography; disappearing stream
13. What are two methods that can be used to determine the flow direction of
streams? Same
14. What is the maximum possible elevation possible of the hill located
approximately at:
W - 30 degrees 28 minutes 50 seconds latitude
N - 79 degrees 57 minutes and 00 seconds longitude
1699 feet
15. What is the horizontal distance (in miles) between Round Hill and Mole Hill?
Approximately 4.5 miles
16. What is the lowest relief of this quadrangle?
< 1170 ft.
17. What is the stream gradient of Muddy Creek from where it reaches Mt. Clinton
(not that one) to where the Rt. 257 crosses it near the town of Montezuma?
155 ft / 5.5 mi = 28.18
18. Normally rivers are fed by runoff and tributaries; however, this map depicts
various rivers in karst topography, where lakes and rivers are fed by disappearing
streams. Find three separate instances of disappearing streams that feed aboveground reservoirs, and provide the longitude and latitude for each.
19. What is the magnetic declination of this map?
20. If the magnetic declination is changing at a rate of 5 minutes west per year, what
is the projected magnetic declination in 2007?
21. Construct a topographic profile between Round Hill and the intersection of Dry
River and Rt. 257.
22. Compare and contrast Dry River and Black’s Run in terms of development and
human interaction.