Transcript PowerPoint Presentation - Oceanic

Oceanic-Continental Convergent
Boundary
By: Nathan Marzoli, Jeff Chagnon
Aaron Phinney, Dan Kunath
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.
Description of an OceanicContinental 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.

Diagrams
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.

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.
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.

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.

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.

The End