Download Constructive and Destructive Forces

Stone Mountain
Gorge
Providence Canyon, GA
Appalachian Mountains
Sand Mountain
Sink-Holes
Beaches
Cumberland Plateau
Lookout Mountain
last battle of Cherokees
Mississippi River
Constructive and
Destructive Forces
What are Constructive and
Destructive Forces?
• Constructive Force
– A constructive force is
a process that raises
or builds up the
surface features of the
Earth.
– Anything that adds or
builds up
• Destructive Force
– A destructive force is a
process that lowers or
tears down the surface
features of the Earth.
– Anything that
subtracts or breaks
down
What Are Surface Features?
– Surface features are landforms and bodies
of water that cover the Earth’s surface
such as:
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mountains
valleys
canyons
gorges
beaches
sand dunes
barrier Islands
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flood-plains
moraines and drumlins
volcanoes
oceans
lakes
rivers
What are Constructive and
Destructive Forces?
What are Constructive and
Destructive Forces?
• Constructive Force
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Deposition
Volcanoes
Crust Deformation
Plate Tectonics
Earthquakes
– Biological!
• Destructive Force
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Weathering
Erosion
Volcanoes
Plate Tectonics
Earthquakes
– Biological!
Introduction to
Topographic
Maps
“Real World”
Contour Map
Topographic Maps
• Contour Line –
- line on a map that connects points of EQUAL elevation.
- show elevation and shape of the land
Topographic Maps
• Contour Interval –
difference in elevation
between each line.
MUST be equal
spacing.
Contour interval =
20 feet
580
560
540
520
Topographic Maps
• Index Contour –
Usually every 5th line is printed darker and has
an elevation printed on it.
Closely Spaced Contours
• Steeper Slope (Gradient) – contour lines are
closer together.
Wide Spaced Contours
• Gradual/Gentle Slope (Gradient) – contour lines
are farther apart.
We build with…
CONSTRUCTIVE FORCES!!
Constructive Forces
Deposition
Volcanoes
Crust Deformation
Plate Tectonics
Biological
Constructive Forces
• Stream Deposition
• As a river moves it picks up sediment and carries it
away
• When that water slows down the sediment drops
and is deposited
– Creates : Floodplains and Deltas
Constructive Forces
Constructive Forces
• Glacial Deposits
• As glaciers move they scrap up huge amounts of
sediment and deposit it where they end
– Creates : Moraine (long, low hill), Karnes
(small hills)
http://videos.howstuffworks.com/howstuffworks/5
2212-glacier-national-park-montana-video.htm
Constructive Forces
Constructive Forces
• Wind Deposit
– Creates : Sand Dunes
• Wave Deposit
– Creates : Beaches, sand bars, barrier islands
Constructive Forces
Constructive Forces
• Volcanoes
– Creates : Islands, New Igneous Rock
• Crust Deformation
– Creates : Hills and Valleys (folding)
Cliffs (faults)
Constructive Forces
Constructive Forces
• Plate Tectonics
– Creates :
• Mountains, Trenches, Volcanoes (convergent)
• Mid-Ocean Ridge, New Rock (divergent)
• Gorges, Cracks (transform)
• Biological
– Creates : Lakes, Rivers
http://animals.howstuffworks.com/28363-fooled-by-nature-beaverdams-video.htm
Convergent
Constructive Forces
Destructive
• Okay FIRST, we need to define something
– Weathering – the process that breaks down land features into
smaller pieces
• Ex. Rain, Acid rain, Wind, Tornadoes, Floods, etc…
– Erosion – the process of moving the sediment from one location
to another
• Ex. Rivers and Streams, Wind, Glaciers, anything that carries the sediment
Destructive
• Weathering & Erosion
– Creates : Canyons, Rivers, Lakes, Gorges
• Volcanoes
– Creates : Craters
Destructive
Destructive
• Plate Tectonics
– Creates : Trench
– Destroys : Old rock
Destructive