Chapter 5 The Changing Surface of Earth

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Chapter 5 The Changing Surface of Earth
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1. Plains Large, relatively flat areas covering
much of the country
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Coastal Plains
plains along coasts
called lowlands because of low elevation (height
above/below sea level)
marshes, swamps, low hills
Gulf coastal plain and  Atlantic coastal plain
Atlantic coastal plain
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Interior Plains
- Great Plains - Central Lowland


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Plateaus
relatively flat, raised areas (raised by
geologic forces)
easy to tell from surrounding area they are
clearly higher in elevation
Colorado Plateau
Colorado Plateau from the Air
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Mountains
Rise high above surrounding area.
We will look at Four types
1. Folded  2. Upwarped  3. Fault-block  4.
Volcanic
Long's Peak, Colorado
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Folded - Mountains

Appalachian Mts.

layers of rock that have been pushed and caused
to fold
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Upwarped




pushed straight up by deep forces from within
Rocky Mts.
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Fault-block
Tilted and pushed, separated by faults (cracks
along which rock moves)
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Fault-block continued
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Volcanic
Molten rock is forced through the crust to the
surface, and builds up
Ash blows through onto the surface and builds up
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Volcanic continued
Sunset Crater, Arizona - a cinder cone
Devil's Tower, Wyo., a Volcanic Neck
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Earth View Points
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Latitude and Longitude
Latitude
distance in degrees north or south of equator
parallel to equator the poles are 90o
Equator imaginary circle around Earth halfway
between the poles
0o Latitude
Longitude
distance in degrees east or west of the prime
meridian
Prime Meridian
It is Perpendicular to equator.
Runs north/south through what used to be the
Royal Observatory in Greenwich, England
0o to 180o
the opposite side of the globe from the 0o of
the prime meridian is 180o, the International
date Line
International Date Line - not an 800 number 180o
longitude, adjusted for local needs
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VIEWPOINTS or How We Look at the Earth and
Manage to Find Anything, Including Ourselves
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Maps
Projections
Earth's surface is curved, so plotting on a flat
map is inaccurate any way you do it.
Most early views of earth were with planar
projections slices either vertical or horizontal
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Projection Types
Mercator - standard flat map
correct shapes of continents, but
areas are distorted
longitude lines are projected parallel to each
other, but

• remember that longitude lines are not parallel -
  they meet at the poles!

• area distortions increase as you get closer to
  the poles

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Robinson
Similar to Mercator, but less distortion near
poles. Continent shapes are foreshortened near
edges and poles.
Longitude lines are projected curved, similar to
the way they would look on a globe
So areas are less distorted near the poles than
with Mercator
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Conic
Used for small areas
Most accurate for the small area
Points from globe projected onto cone-shaped
paper later laid flat
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Topographic Maps
Show changes in elevation of earth's surface.
Contour lines
lines on a map that connect points of equal
elevation
Contour interval
the difference in elevation between two
side-by-side    contour lines
Index contours
contour lines marked with their elevations.
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Rules for Contour Maps
1. The difference between a hill or a depression
closed lines will be used for both hills and
depressions
BUT around a depression, short lines (called
hachures) perpendicular to the contours will be
shown pointing downhill.
2. CONTOUR LINES NEVER CROSS A particular
spot can't have more than one elevation!
3. Distance between Contour Lines shows slope.
Contour lines that are closer together mean  
land is steeper. 
Contour lines that are farther apart mean land
is less steep. 
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Rules for Contour Maps cont.
4. Contour lines form V 's that "point" upstream,
wherever they cross rivers and streams.
If you walk straight across a stream, you go
downhill to the stream. Then you go uphill as you
walk away from the stream. If you wanted to walk
at the same elevation, you would have to go
upstream, then back downstream, to do so.
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Map Legend

• Legends, explain symbols and meaning of them.
• Scale used to measure distances on maps.
• 180,000 this scale means that 1 unit on the map
  represents 80,000 units on land.

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Time Zones

• Earth rotates once every 24 hours
• 24 Time zones
• Time zones are 15 degrees wide
• 6 Time zones in the United States
• Time zones lines are relative to lines of
  longitude. (outside cities)

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International Date Line

• The 180 degree meridian
• West of the IDL, advance 1 day
• East of the IDL, back 1 day