PLATE BOUNDARIES AND THE LANDFORMS THEY CREATE

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PLATE BOUNDARIES AND THE LANDFORMS THEY CREATE
DIVERGENT CONVERGENT TRANSFORM
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Vocabulary
Plate Boundaries--The location were two plates
meet. Divergent boundaries -- where new crust
is generated as the plates pull away from each
other. Convergent boundaries -- where crust is
destroyed as one plate dives under
another. Transform boundaries -- where crust is
neither produced nor destroyed as the plates
slide horizontally past each other.
Plate-Boundary zones--broad belts in which
boundaries are not well defined and the effects
of plate interaction are unclear.
Experience different plate
boundaries


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Oceanic-continental convergence--Where the plate
that is covered by water and the plate that is
covered by land meet. Oceanic-Oceanic
Convergence--when two oceanic plates converge,
one is usually sub ducted under the other, and in
the process a trench is formed. Continental-Conti
nental convergence-- When two continents meet
head-on, neither is sub ducted because the
continental rocks are relatively light and, like
two colliding icebergs, resist downward motion.
Instead, the crust tends to buckle and be pushed
upward or sideways.
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Transform Boundaries
Transform Boundaries -The zone between two
plates sliding horizontally past one another.
-A transform boundary is said to occur when
tectonic plates slide and grind against each
other along a transform fault. -Concept
originated by Canadian geophysicist J. Tuzo
Wilson -Offset the active spreading ridges
and produce zig-zag plate margins defined by
shallow earthquakes. -Example is the San
Andres Fault in California -Cause a lot of
Earth Quakes -The Great San Francisco
Earthquake of 1906
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Convergent boundaries
Convergent Boundaries -the location where
sinking of a plate occurs is called a subduction
zone -Convergence is a very slow collision
of plates -There is three types of
convergent boundaries Oceanic-Continental
Convergence -Trenches are created by
subduction -One plate is being subducted
under another -One example is when the Naza
Plate bumps into the South American Plate and is
being subducted under. The Andes Mountains were
created as the S.A. Plate rises. This causes
major earthquakes
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Oceanic- Oceanic Convergence -A trench is
formed when one plate is subducted and two
oceanic plates converge. -One example is
Marianas Trench -Formed where fast
Pacific Plate converges against the slower
Philippine Plate -This convergence results
in volcanoes. -Many volcanoes (like Hawaii)
are situated on island arcs that are really
trenches that was created by convergences!
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Continental-Continental Convergences -
Himalayan Mountain is formed by the Eurasian
Plate overriding the Indian Plate 50 million
years ago! -Mountain ranges like the Alps
and the Rockies were formed this way.
-Powerful collision -Because the density of
the plates is lower than the mantle, subduction
is prevented. A mountain is formed because
subduction is difficult
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Divergent Boundaries
Divergent boundaries -- where new crust is
generated as the plates pull away from each other.
Occurs along spreading centers were plates are
moving across and new crust is being created when
magna pushes up from the mantle.
Example is the Mid-Atlantic Ridge--this is a
mostly underwater mountain range that runs
through the Arctic and Atlantic Oceans.

• An example of the effects of divergent boundaries
  is Iceland which is split in half by the
  Mid-Atlantic Ridge and will eventually split in
  half as the Ridge expands.

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HISTOICAL INFORMATION ON PLATE BOUNDARIES The
scientist who began the research on Plate
boundaries was Alfred Wegener. He came up with
the theory that at one point in time all the
continents were one. He arrived at this theory
when he red a report talking about how some of
the same types of plant and animal fossils were
being found on opposite sided of the Atlantic
ocean. He began to study the continents and
noticed how they looked as if at one time they
could have all fit together. Many scientists
thought this was not at all a logical theory and
rejected the idea all together, but eventually
the idea gained more support as time went on.
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REAL LIFE APPLICATIONS

• Plate movement cause a lot of natural disasters
• Plate movement can cause large cracks in the
  surface, earthquakes, and fissures
• Plate also create mountains by pushing up on each
  other.
• Volcanoes can erupt from plate movement
• Geodesy is the study of the size and shape of
  earth
• People study plate boundaries with geodesy
• Scientist can study plate boundaries on the
  ground but the best way is through a satellite.

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Bibliographical Information

• Watson, Jim. "Understanding Plate Motions." USGS.
  05.05.99.USGS. 1 Oct 2007 lthttp//pubs.usgs.gov/gi
  p/dynamic/understanding.htmlgt. Loomis,
• Jennifer. "Observe animations of processes that
  occur along plate boundaries." Exploring Earth.
  Exploring Earth . 1 Oct 2007lthttp//www.classzone.
  com/books/earth_science/terc/content/visualization
  s/es0804/es0804page01.cfm?chapter_novisualization
  gt.
• "Understanding Plate Motions." UsgaScience for
  changing the world. 5/5/99. Usga.
  lthttp//pubs.usgs.gov/gipgt.
• King, Hobart. "Teaching Plate Tectonics with."
  Geology.com. Geoglogy. 2 Oct 2007
  lthttp//geology.com/nsta/transform-boundary.gifgt.
  
• "Wikipedia." Transform Boundary. 9/11/07.
  Wikipedia. 2 Oct 2007 lthttp//en.wikipedia.org/wik
  i/Transform_boundarygt.
• King, Hobart. "Convergent Plate Boundaries."
  Geology.com. 2005-2007. Geology. 2 Oct 2007
  lthttp//geology.com/nsta/convergent-plate-boundari
  es.shtmlgt.
• King , Hobart. "Convergent Plate Boundaries."
  Geoglogy.com. Geology.com. 2 Oct 2007
  lthttp//geology.com/nsta/convergent-plateboundary-
  oceanic-continental.gifgt.
• Glasscoe, Maggie. "Education Module." Glossary of
  Terms. 8/13/98. Maggi Glasscoe. 2 Oct 2007
  lthttp//scign.jpl.nasa.gov/learn/glossary.htutwen
  tyonegt.
• Glasscoe, Maggi. "Plate Boundaries." The Southern
  California Intergrated GPS Network Education
  Module. 9/8/98. Scign Education Module. 2 Oct
  2007 lthttp//scign.jpl.nasa.gov/learn/plate4.htmgt.
  

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• Glasscoe, Maggi. "Plate Boundaries." The Southern
  California Intergrated GPS Network Education
  Module. 9/8/98. Scign Education Module. 2 Oct
  2007 lthttp//scign.jpl.nasa.gov/learn/plate4.htmgt.
  
• "How Volcanoes Form." Volcanoe Word. 8/4/07.
  University of North Dakota. 2 Oct 2007
  lthttp//volcanoe.und.edugt.
• Waggoner, Ben. "Alfred Wagner 1880-1930." Berkely
  . 06/09/96. Berkely.edu. 2 Oct 2007
  lthttp//www.ucmp.berkeley.edu/history/Wagener.html
  gt.
• "Plate Tectonis." Wikipedia. 9/28/07. Wikipedia.
  2 Oct 2007 lthttp//en.wikipedia.org/wiki/Plate_bou
  ndariesgt.
• "Understanding Plate Motions." USGS. 05/05/99.
  Usgs. 2 Oct 2007 lthttp//pubs.usgs.gov/gib/dyhomic
  /understanding.htmlgt.
• Viau , Elizabeth Anne . "Tectonic Plates." World
  Builders. 2003. world Builders. 2 Oct 2007
  lthttp//curriculum.calstatela.edu/courses/builders
  /lessons/less/les2/tectonic.htmlgt. .
• "Plate Tectonics." Indiana . 2 Oct 2007
  lthttp//www.indiana.edu/geol116/week7/week7.htmgt.
  
• "Shifting and Sliding." The Tech. The Tech. 2 Oct
  2007 lthttp//www.thetech.org/exhibits/online/quake
  s/plates/tectonics.htmlgt.
• "Divergent Plate Boundaries." USGS. 1/14/1999.
  USGS National Park Service. 2 Oct 2007
  lthttp//www2.nature.nps.gov/geology/usgsnps/pltec/
  diverge.htmlgt

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Plate Boundary Demo
Divergent Boundary Exercise -You can
simulate divergent plate motion by placing your
palms down with your index fingers touch. Now
pull your hands apart. Convergent Boundary
Exercise -You can simulate convergent plate
motion by placing your hands together in front of
you with your palms down. Now gently slide your
bottom hand downward and your top hand upward,
while keeping them in contact. Transform
Boundary Exercise -You can simulate
transformational plate motion by placing your
hands together in front of you with your palms
down. Now slide your left hand away from you and
your right hand toward you.