The USGS publishes approximately 57,000
different topographic maps covering the USA. Topographic maps
include contour lines indicating landforms and elevations, hydrography
(rivers, lakes, marshes, transportation (roads, trails, railroads,
airports), vegetation, boundaries, survey markers, urban areas,
buildings, and a variety of other features. These maps are
drawn according to the National
Map
Accuracy Standard and are most commonly published at
1:24,000, 1:100,000, 1:250,000, and 1:500,000-scale,
although many
other scales exist as well.
Topographic maps represent a fantastic
resource for educators. They
can be used in a variety of ways in the
science, math, geography, and
history curriculum, from elementary to
college level. The following ideas
have been compiled by Joseph
Kerski to be used as an aid in building
educational lessons.
Topographic Maps Tutorial from the Geospatial Training and Analysis
Cooperative, Idaho State University: Includes sections devoted to `What is a Map?,
Reference Datum, Map Projections, Distortions, Grid Systems, Geographic
Coordinates, UTM, State Plane, Public Land Survey, Using Topo Maps, Map Scale,
Magnetic Declination, Vertical Scale, Creating Profiles, Vertical Exaggeration,
Calculating Slope, Using a Compass, Setting Magnetic Declination, Get a Bearing,
Go from A to B, Find Self on a Map, and four field exercises using topographic
maps.
http://geology.isu.edu/geostac/Field_Exercise/topomaps/index.htm
Dr Slaymaker's Topographic Maps
and Aerial Photographs Web Pages:
http://www.csus.edu/indiv/s/slaymaker/
Educational Map Catalog:
http://rockyweb.cr.usgs.gov/public/outreach/mapcatalog/
USGS Map Store:
http://store.usgs.gov
Sample images from USGS Topographic
Maps:
Visit:
http://mapping.usgs.gov/mac/isb/pubs/booklets/usgsmaps/usgsmaps.html
How To Obtain Topographic Maps:
Visit http://mapping.usgs.gov/mac/findmaps.html
Topographic Map Symbols:
Visit http://mapping.usgs.gov/mac/isb/pubs/booklets/symbols/index.html
1. Global Positioning System and
Coordinate Systems
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, GPS receiver, metal dividers
for interpolation (optional) |
1 - 3 hours |
Divide students into groups and have them
determine, to the nearest second,
the latitude and longitude of the school using a 1:24,000-scale topographic map
covering the school and surrounding area. Discuss need for
accuracy. Use a 1:100,000 and a 1:250,000-scale map of the same area and
discuss the difficulty of determining position depending on the map
scale.
Discuss base 60 with reference to time, and transfer discussion
to base 60 with latitude-longitude degrees-minutes-seconds. Discuss the
process of interpolation. Draw a 2.5-minute grid on interior of USGS 1:24,000-scale
topographic map using 2.5-minute tic marks on margin of map as a guide. Write answers
from all teams on the board.
Next, go outside
and record positions with GPS receiver;
stay out at least 10 minutes for
the most accurate averaging. Go
back to classroom. Compare reading
from GPS receiver to that of each
team. Which team was closest?
Repeat the above with the UTM (Universal
Transverse Mercator) coordinate system.
UTM coordinates are drawn in blue tic
marks with a 10,000 meter interval.
Compare the convenience of units expressed
in meters with
UTM versus those expressed in seconds
(with lat/long).
Discuss the accuracy of your GPS unit.
Discussion: Oftentimes the students
will be too willing to discard their own
interpolations from the topographic map
and willing to accept a high-tech
device, despite its accuracy limitations
(particularly a low-end unit).
Many times, the student's interpolations
will be more accurate,
particularly with the z reading (elevation).
Discuss why this is so -
triangulation with satellites, Selective
Availability error code with
units, obstruction by buildings, limited
time to collect coordinates, etc.
2. Locating Benchmarks - Surveying
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, benchmark (optional) |
1 - 2 hours |
Materials Required: Topographic map,
benchmark (optional).
Discuss benchmarks - why they are important
in mapping, to make maps
more accurate in x , y, and z. Why
do peoople demand accuracy in maps?
Discuss the uses of maps, and which data
users require accuracy. Discuss
laying of pipeline requirements as opposed
to locating climatic zones.
If possible, obtain a benchmark from surveying
company or catalog and
show class.
Show topo map symbols sheet and have students
find benchmarks on
map. Discuss why certain areas (tops
of mountains, railroad track sidings,
etc) are better for locations to mount
benchmarks than others.
Discuss the permanency vs transitory nature
of these features vs mounting
the benchmark in sand or in a tree.
Look at the http://www.ngs.noaa.gov
site
at the National Geodetic Survey for
discussion on surveying. Discuss
triangulation and leveling techniques.
If possible, go on field trip and try
to find one or more of the
benchmarks the students have found on
the topographic map.
3. Geographic Coordinate System
- Convergence
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, globe |
1 hour |
Discuss the convergence of longitude lines
at the poles by illustrating the concept first on a globe.
Show topographic maps in North Dakota versus those in Louisiana or Hawaii,
illustrating why those in North Dakota
are narrower in the east-west direction
than Louisiana/Hawaii. Measure the differences. Discuss: Why don't
the latitude lines converge?
4. Comparing Coordinate Systems
| Grade Levels |
Materials Required |
Time Required |
| Middle School - College |
Topographic map, USGS UTM fact sheet,
map in Cartography book (such as Muerhke's Map Use book) showing state
plane coordiinates |
1 - 3 hours |
Discuss geographic coordinate system (lat/long)
vs UTM (use USGS fact sheet on UTM coordinate
system) vs state plane
coordinates. Use state highway maps
or other state-based maps or county
maps in state plane coordinates. Why are map projections used? What
is the relationship between map projections and coordinate systems? Why are different systems used? Who
are the data users that require one over
the other? Discuss state vs
global needs. When does coordinate
system have an advantage over another?
5. Precision of Coordinates
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map |
1 - 2 hours |
Discuss precision of lat/long readings,
and why hours has to be divided up
into minutes and seconds for precision.
Analogy: If I were to meet you
after school, I might say 4:00pm, and
if you and I showed up at 3:58 or
4:02, it would not be that important.
However, if you were launching the
space shuttle, it is critical that you
state the launch will be at
4:00.0355. In the same way, if you
were constructing a pipeline you would
need more than degrees of lat/long, you
would need precision down to the
tenths of a second of latitude and longitude
of its location.
6. Absolute versus Relative Location
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map |
1 hour |
Discuss absolute location versus relative
location. What is the
difference between 42 07 31" lat / 101
15 31" long versus the phrase
"northeast of Pleasant Grove"? When
is absolute location important, and
when is relative location important? Which one(s) does GPS measure?
7. Map Projections
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, globe, USGS poster or
other illustration of map projections |
1 - 3 hours |
Ask students to examine the map projection
of the chosen topographic
map and other maps. Discuss the
advantage and disadvantage of different
map projections. Why do Greenland
and Canada look so large on a Mercator
projection? Illustrating distortion
with map projections is great to do
with a GIS by drawing a circle and seeing
how it is distorted with
different projections, and how the distance
from Honolulu to Los Angeles
varies, and how the angle varies.
Show globe and topographic maps. Why
does the process of drawing the earth
on a two dimensional piece of paper
cause distortion?
Use USGS poster (available from the USGS)
on map projections as well as
cartography texts to illustrate how distance,
direction, angle, or area
have to be distorted. When is it
best to distort
distance/direction/angle, or angle?
If you had to choose 3 of the 4
attributes to keep accurate, what would
they be?
Illustrate how choosing the map projection
depends on the application.
Illustrate how the projection of the map
is more evident on a
small-scale than a large- scale map.
If possible, read sections of book "How
to Lie with Maps"
(Monmonier).
8. History of Cartography
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, other maps, USGS "Exploring
Maps" Teachers Packet |
1 - 4 hours |
Examine how maps were made in the past.
Obtain some negatives and
scribing materials from a film or drafting
company. Obtain a scribing
instrument; a sharp nail or compasses
end will suffice.
Pencil in some contour lines on the film
and have students try to follow
them with the scribing instrument.
Discuss the fact that most
topographic maps were prepared using manual
scribing instruments.
Ask why film was used rather than paper.
Discuss the national map
accuracy standards and the scientific
principal of shrinking and swelling
of materials with temperature. Film
shrinks and swells less than paper.
Use USGS Teachers Packet "Exploring Maps."
This packet contains
two posters illustrating historical maps
back to the Babylonians.
Use samples from "Mercator's World" or
other historical map journal.
Illustrate with samples from the Library
of Congress map WWW page.
9. Modern Cartography
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, GIS software (optional) |
1 - 3 hours |
Discuss geographic information systems
(GIS) ,
and the capability of drawing all points,
lines, and areas on the
computer. Ask the students what
the advantage is of making maps on the
computer vs by hand. Advantages
include the ability to easily change the
symbology, projection, scale, and then
to have the map layers available
for analysis in a GIS.
Visit WWW sites running Internet map server
software, where students can construct
a map with a web browser. Look at
http://rockyweb.cr.usgs.gov/public/outreach/
for a list of some of these
sites.
10. Aerial Photo Interpretation
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, USGS or other aerial
photographs |
1 - 4 hours |
Obtain an aerial photograph of an area
from the USGS
(use PhotoFinder at
http://edc.usgs.gov/Webglis/glisbin/finder_main.pl?dataset_name=NAPP)
and then a topographic map covering the
same area. Ask
students how they can identify a stadium,
lake, school, office building,
stream, mountain, and other features on
an aerial photograph. The world
is more complex than is at first realized.
Schools may have an athletic
track if a high school, but what about
in a dense urban area? Do they
always have a track?
Ask students to identify the time of year
that the photograph was taken.
What are the clues? Ask students
to identify the time of day the
photograph was taken? What are the
clues? What is the best time to take
a photograph if you were going to make
a map from the photograph? Near
solar noon is best to minimize shadow.
Near the summer solstice is best
also to minimize shadow, except in heavily
timbered areas, when "leaf-off"
times are best in March and November.
11. Analysis of Stereo Aerial
Photographs
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, USGS or other aerial
photographs, stereoscope |
1 - 4 hours |
Discuss the need to see the world in
three dimensions for creating contour
lines. Show "magic eye" images.
Can the students see them in three dimensions?
Obtain stereo viewer and
obtain stereo aerial pairs. Hubbard
Scientific is one vendor of these.
If students have difficulty, tape the
photographs on the table in the correct
overlap position. Use the aerial
photo finder at the USGS
at http://edc.usgs.gov/Webglis/glisbin/finder_main.pl?dataset_name=NAPP
to illustrate the concept of
consecutive photographs along a single
flight line to obtain stereo.
12. Creating Maps from Aerial
Photographs
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, other types of thematic
maps, aerial photographs |
1 - 3 hours |
How should each feature be mapped such
as the map doesn't become
too complicated or cluttered? Use
topographic map symbols. Make maps with TODALSIGS--Title, Author, Date,
Author, Legend, Scale, Index, Grid, Source. How can
students decide which features should be
mapped? Discuss the reason why the
real world needs to be simplified to
make a map. For every theme that
is drawn on a map, there are themes that
are omitted (for example, soils).
13. Analyzing Physical Features
on Topographic Maps
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic maps at a variety of scales. |
Expandable from 1 hour to several weeks. |
Examine at the list of physical features
on
http://rockyweb.cr.usgs.gov/public/outreach/,
such as eskers, drumlins, glaciers, bajadas,
canyons, mesas, coastal features,
sand dunes, marshes, floodplains, volcanoes,
alluvial fans, karst, and so
on. How are these features identifiable
on topographic maps?
What are the sizes of each of these features?
What is the most suitable
scale with which to examine the entire
physical feature? How do physical features affect population settlement
amount and patterns?
14. Analyzing Change on Topographic
Maps
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Historical and current topographic maps
from USGS or other historical maps |
Expandable from 1 hour to 1 week. |
Obtain historical prints of topographic
map from USGS, and
compare to latest printed edition.
What
are the reasons for land use change? Which areas change much, and which
areas change little, and why? From what direction and what is the
magnitude of the forces that cause land
use change, locally, regionally,
and nationally? Examine 1:24000,
1:100,000, and 1:250,000-scale maps to
answer these questions. For example,
is there an urban area to the west
of the area under study that is causing
the changes?
Discuss physical changes versus human-caused
change.
Examples of maps with physical
changes include Earthquake Lake MT, South
Pass LA, and Mt St Helens, WA.
Examples of maps with human-caused change
include any map containing a
reservoir or urban area. Have students
speculate and draw what the area
will look like in 10, 20, and 30 years
from now. Look at the Map Mysteries
lessons on http://rockyweb.cr.usgs.gov/public/outreach/mapmys.html
for more ideas.
15. Analysis of Impact of Public
Land Survey System (PLSS)
On the American Landscape
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic maps of PLSS and non-PLSS
states; map showing PLSS states |
1 - 3 hours |
Discuss the 1785 Ordnance Survey that Jefferson
signed into law. Obtain "baselines and
meridians" Public Land Survey map from USGS that shows the
spread of the township and range
system for dividing up land for settlement,
beginning in Ohio and
spreading west. Discuss why Texas
has no PLSS (separate country for a
time). What is the impact of this
system on the rural landscape? Compare
land in Virginia - - roads and boundaries
- - versus that in Kansas. What
is the impact of this system on the urban
landscape? Show maps of cities
in PLSS states versus cities in non-PLSS
states. Note, for example, the
regular grid in Phoenix vs the irregular
pattern of Atlanta. Emphasize how
an act from 1785 continues to affect the
routes we took to get to school
today! Illustrate this land division
versus long lot system of the lower
Mississippi River floodplain.
16. Creating Profiles
| Grade Levels |
Materials Required |
Time Required |
| Middle School - College |
Topographic map, rulers. |
2 - 4 hours |
Draw cross-sections (profiles) along several
transects across
the topographic map, from analyzing contour
lines. Where is the topography
steepest? Flattest? Why?
What forces are most active on the landscape
in this area?
Landslides? Floods? Erosion?
Tectonism? Coastal storms?
What forces were most active in the past?
Glaciation? Were the past
forces the same as today's forces?
Compute the slope in percent and in degrees.
Have
students plan a railroad and a road from
point A to point B through a
mountainous region. Give students
a constraint of 8% for the maximum road
grade and 2% for the maximum railroad
grade. Compare students routes.
Show map with railroad on it in another
area, and have students compare
the number of twists and turns, and calculate
distance, between roads and
railroads.
17. Analysis of Map Scale Using
Point Reyes, California
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic maps at different scales. |
1 - 3 hours |
Discuss map scale. Large scale map
1:24,000 is a larger number
(fraction) than a small scale map (1:100,000).
When would you need a map
at a large scale versus a small scale?
One example of scale difference in
answering a question: Is California splitting
off into the Pacific Ocean?
Examine Point Reyes CA map. At this
scale, yes, it is "splitting", in the
sense that the land over the San Andreas
Fault has sunk to the point where
the Pacific Ocean has flooded the area.
At a smaller scale, no, the land
is not "splitting off" into the Pacific
Ocean.
18. Analyzing Cultural Features
on Topographic Maps
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
1:24,000-scale topographic maps from a
variety of areas, both urban and rural. |
Expandable from 1 hour to several weeks. |
What are the major commercial activities
of the area shown on the
selected topographic map? How are
these activities reflected in the
cultural, or human-built, features on
the map?
Why do people want to move to this area?
Is this
a fast or slow-growing, or declining,
area, and why? What forces act to limit or promote growth?
Why are certain land uses concentrated
in certain areas? For example,
what kind of buildings are near railroad
tracks? Near stadiums?
Near universities? Near interstate
highways? Why?
19. Analysis of Scale
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic maps at different scales. |
1 - 5 hours |
Examine scale difference. Obtain
different USGS maps of the same area.
How large is Lincoln Nebraska on a 1:24,000-scale
vs a 1:100,000-scale
vs a 1:250,000- scale vs a 1:500,000-scale
state base map, and what
accounts for this difference?
20. Construct Plaster 3D Models
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, plaster of Paris or other
modeling material, water, tray |
1 - 3 hours |
Construct plaster models of areas on topographic
maps. Flood one
inch, draw a contour line in marker, flood
one more inch, draw another line, etc.
Remove water, look at lines from above,
to illustrate the concept of
contour lines.
21. Analysis of Urbanization Over
Time
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic maps of an urban area at 1:24,000
and 1:100,000 scale. |
1 - 5 hours |
Examine older vs newer urbanization.
How do you know which is older? What are the differences in the street pattern,
and why? Discuss how and why the chosen urban area
first began, and how and why
it spread. In which direction(s)
is it growing, and why? Was there a river
or other physical feature that helped
the urban area get its start?
Why is older urbanization usually along
straight streets and
with smaller homes, vs newer urbanization?
Discuss popular culture
and consumer preferences.
22. Create Slope Maps
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, sheets of poster paper. |
1 - 3 hours |
Create slope maps by examining contour
lines. Divide the map area into
categories and use a symbol identifying
the slope in that area. Use a
smaller area of the topographic map if
the relief is too complex. Use
categories 0-5%, 6-10%, etc, or other
interval depending on map selected
and create polygons where the slope falls
within these categories. What
is the relationship of land use to slope?
What slopes are most human
settlements located on?
Obtain USGS Slope map of San Francisco
and
compare. Does slope influence land
use in San Francisco? What slopes
are the tall downtown buildings located
on, and why?
23. Create Aspect Maps
| Grade Levels |
Materials Required |
Time Required |
| Middle School - College |
Topographic map, sheets of blank poster
paper. |
1 - 3 hours |
Make aspect maps by examining contour lines.
Aspect refers to the
direction (north, east, south, west) that
the slope faces. Compare the
vegetation on north-facing versus south-facing
slopes. What aspects are
ski areas usually built on? Why
are ski areas usually located on north-
facing slopes? Discuss microclimates
of slopes.
Where would they be located in the southern
hemisphere?
Discuss earth-sun relationships.
24. Analysis of Humans and Hydrography
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map, GPS receiver, metal dividers
for interpolation (optional) |
1 - 3 hours |
Discuss floodplains, rivers, and settlement.
How do rivers both encourage
(with trade and traffic) and discourage
(with flooding) settlement?
Why does one bank of a large river attract
a large city,
while the other bank is sparsely populated?
This may occur if one bank
was higher and flood-free, and the other
was flood-prone.
What is the elevation of both banks?
Discuss the importance of a city
site to be on a flood-free site, higher
than the floodplain.
25. Site versus Situation
| Grade Levels |
Materials Required |
Time Required |
| Elementary - College |
Topographic map of New Orleans West and
other locations. |
1 - 3 hours |
Site refers to the physical attributes
of a location, such as
tica">drainage, climate, and so on. Situation
refers to the advantages and disadvantages
of one location over another
location, considering trade routes, transportation,
and so on.
Discuss site versus situation with topographic
maps at different
scales.
Examine the New Orleans West, Louisiana 1:24,000-scale
map. Note the
amount of land below sea level.
Discuss draining of the land for a city site on a river delta. Discuss site versus situation
here and elsewhere. New Orleans is a
poor site (prone to flooding) but has
a good situation (near the mouth of
a large river). Discuss the impact of global sea level rise on New
Orleans. Discuss another
location that is a good site but a poor
situation (for example, a well-drained
location in the middle of plain,
far from an overland route or river).
U.S. Department of the Interior
U.S. Geological Survey
Rocky Mountain Mapping Center
Maintainer:webmaster@rockyweb.cr.usgs.gov
URL:http://rockyweb.cr.usgs.gov
/public/outreach/topoteach.html
Last modified: 17 February 2004