Oceanic-Continental Convergent Boundary

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Oceanic-Continental Convergent Boundary

• By Nathan Marzoli, Jeff Chagnon Aaron Phinney,
  Dan Kunath

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What is an Oceanic-Continental Convergent
Boundary?

• A Oceanic-Continental Convergent Boundary is a
  type of convergent boundary. A convergent
  boundary occurs when two plates move towards each
  other.
• At this type of boundary, old rock is recycled as
  the oceanic plate is forced under the continental
  plate.

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Description of an Oceanic-Continental Convergent
Boundary

• This type of boundary occurs when a more dense
  oceanic plate is moving towards a continent.
  This continent is made up of a continental plate.
  These two plates are moving towards each other.
  When they collide, the more dense oceanic plate
  sinks down below the continental plate. As it
  sinks down, it causes a series of earthquakes.
• At these types of boundaries, volcanic mountain
  arcs are formed when the two plates collide.
  Examples of these volcanic mountain arcs are the
  Cascade Mountains, of which Mount St. Helens is
  part of in Washington.

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Diagrams
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Convection Currents

• Convention currents occur when cooler magma
  sinks down below the surface, then rises back up
  to the surface as warmer magma.
• When the hot magma rises to the surface, it
  pulls the plates in the area with it. They then
  travel across the surface and sink when the magma
  cools, dragging the plates along with it.

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Geological Feature That Forms At This Boundary

• The Geological feature that forms at these types
  of boundaries would be volcanic mountain arcs.
  They rise up out of the continent as mountain
  ranges, but actually are volcanic and are known
  to spew out lava at any time.

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Two Locations On Earth Where This Type of
Boundary Exists

• Where the Juan de Fuca plate plunges under the
  North American plate. This occurs along the
  coast of the North Western United States.
• Another location is where the Nazca plate sinks
  underneath the South American plate, which forms
  the Andes Mountain Range.

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Vocabulary

• Plate- One of thirteen different sections of the
  lithosphere that move about the surface of the
  asthenosphere.
• Lithosphere- The rigid outer layer of the earth,
  including the curst and uppermost mantle.
• Asthenosphere- A layer of hot, weak material
  located in the mantle between a depth of 100 and
  350 kilometers. The rock within this zone is
  easily deformed.
• Mantle- The most voluminous layer of the earth
  located between the crust and core.

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Vocabulary (Continued)

• Converging Boundary- A boundary in which two
  plates move together, causing one of the slabs to
  be consumed into the mantle as it descends
  beneath an overriding plate.
• Crust- The very thin outer layer of the earth.

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The End