GEOG 310: Introduction to Computer Mapping and GIS
GIS Lab Exercise #9: Map Analysis Using Paper and Digital USGS Topographic Maps
-- There are three primary objectives for this week's GIS lab exercise:
Learn how to determine locations on paper USGS topographic maps (1:24000 scale), and learn how
to interpret elevation contour lines on these maps.
Learn how to interpret and map elevation contour lines on digital topo maps using ArcMap and ArcScene.
Learn how to measure distances and areas on digital topo maps using the TerraGo Toolbar in Adobe
Important rules for this week's mapping exercises:
For this week's assignment, you are going to work in a group of 2 or 3 people to answer these
questions and make maps.
All topo map work, paper and digital, is group work for this week. Please
make sure that you are critical of your groups' answers and maps.
Do not assume that the answers are
correct, or the map is good, just because you think a "smart" person seemed to be in charge
If you must sketch on the maps, use very light and small pencil marks, and carefully erase all marks.
For the questions #4, 5, 7, and 13, you must show your calculations as well as the answers for full credit!
This means one set (per group) of neat, legible, handwritten calculations written on separate sheets of paper.
Neatly write all final answers on the answer sheet provided for this lab assignment.
The total point value per numbered question is shown in [brackets].
What is the location, to the nearest ¼ ¼ section, of the confluence of Lightner Creek with Wildcat Canyon?
To a hydrologist or river rat, a "confluence" is where two streams join together.
This confluence is just
north of the Wildcat Canyon Road and U.S. Highway 160 intersection.
Use the legal township & range
Way back in 1963, when the information on this map was last field checked, what type of piscine activity
went on in the E½ of Section 8, T35N, R10W?
Along U.S. Highway 160, what is the distance in miles from the Animas River to the town of Mancos?
Round your answer to the nearest 1/10 mile.
What is the elevation difference?
To reasonably answer
these two questions, open
in ArcMap, and zoom into the Durango
West map so that you can see all of Highway 160.
Click the Measure tool
In the Measure tool
window, set the measurement units to miles.
Move the cursor to Highway 160 just across from the
Start digitizing the highway using a point-and-click method.
Double click to end the line.
The distance in miles will be shown in small text on the Measure tool.
Remember, you need to
determine the distance along Highway 160 from the Animas River to Mancos.
You do not, however,
need to digitize the entire highway length.
Look for a hint (in red text) at the western edge of the
Durango West map where the highway meets the neatline border.
This hint is also printed on the paper
For the elevation difference question, assume the elevation of Mancos is the number listed next
to the town name on the digital Mancos map.