Page 256 - Laboratory Manual in Physical Geology

ACTIVITY ACTIVITY

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9.1 Map and Google Earth 9.2 Map Locations, Distances,
Inquiry Directions, and Symbols

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THINK How are specific places and THINK What coordinate systems, scales,
About It quadrangles located using the latitude- About It directional data, and symbols are used
longitude coordinate system, and how on maps?
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| could geologists use Google Earth to
study them? OBJECTIVE Identify and characterize features on

topographic maps using printed information, compass
OBJECTIVE Apply the latitude-longitude coordinate bearings, scales, symbols, and three geographic

system to locate a country, quadrangle, and place systems: latitude and longitude, the U.S. Public Land
of your choice, and then explore it in greater detail Survey System (PLSS), and the Universal Transverse
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using Google Earth tools, layers, ruler, and historical Mercator System (UTM).
imagery.
PROCEDURES
PROCEDURES 1. Before you begin , read the following topics
1. Before you begin , do not look up defi nitions and below: Introduction, Latitude-Longitude and
information. Use your current knowledge, and Quadrangle Maps, Map Scales, Declination and
complete the worksheet with your current level of Compass Bearings, Global Positioning System
ability. Also, this is what you will need to do the (GPS), UTM—Universal Transverse Mercator
activity: System, and Public Land Survey System. Also, this
____ Activity 9.1 Worksheet (p. 249 ) and pencil is what you will need :
____ computer with Internet access (on which ___ Activity 9.2 Worksheet (p. 251 ) and pencil
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Google Earth software is, or can be, ___ calculator
loaded)
2. Then follow your instructor’s directions for
2. Complete the worksheet in a way that makes completing the worksheet.
sense to you.
3. After you complete the worksheet , be
prepared to discuss your observations and ideas
with others. ( FIGURE 9.1B ) is a flat representation of Earth’s surface that

shows horizontal (two-dimensional) positions of features
like streams, landmarks, roads, and political boundaries.
A topographic map shows the same horizontal informa-
Introduction tion as a planimetric map but also includes contour lines
Imagine that you are seated with a friend who asks you to represent elevations of hills and valleys. The contour
how to get to the nearest movie theater. To find the lines are the distinguishing features of a topographic map
theater, your friend must know locations, distances, and and make it appear three dimensional. Thus topographic
directions. You must have a way of communicating your maps show the shape of the landscape in addition to
current location, the location of the movie theater, plus horizontal directions, distances, and a system for describing
directions and distances from your current location to the exact locations.
movie theater. You may also include information about the Most United States topographic maps are published by
topography of the route (whether it is uphill or downhill) the U.S. Geological Survey (USGS) and available at their
and landmarks to watch for along the way. Your directions US Topo website ( http://store.usgs.gov ). Canadian topo-
may be verbal or written, and they may include a map, graphic maps are produced by the Centre for Topographic
satellite image, or aerial photograph (picture taken from an Information of Natural Resources Canada (NRCAN:
aircraft). Geologists are faced with similar circumstances in http://maps.nrcan.gc.ca ). State and provincial geological
their field (outdoor) work. They must often characterize surveys, and the national geological surveys of other coun-
geologic features, the places where they occur, and their tries, also produce and/or distribute topographic maps.
sizes, shapes, elevations, and locations in relation to other
features. Satellite images and aerial photographs are used to Latitude-Longitude and
view parts of Earth’s surface from above ( FIGURE 9.1A ), and
this information is summarized on maps. Quadrangle Maps
A map is a flat representation of part of Earth’s Earth is a spherical body or globe, and specific points
surface as viewed from above and reduced in size to fit a on the globe can be defined exactly using a geographic
sheet of paper or computer screen. A planimetric map coordinate system in which points are defined by the

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