Download Subduction zones

Converging Plate Boundaries
http://library.thinkquest.org/17457/platetectonics/4.php
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Plates are created and grow at diverging plate boundaries.
Plates come together and are destroyed at converging plate
boundaries.
The great pressures exerted when plates collide create spectacular
features.
Converging plate boundaries are divided into two categories:
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Subduction zones
Collision zones
Subduction zones develop where oceanic plates collide with continental
plates. The oceanic plate is comprised of heavier basaltic rock and descends
below the continental plate. The oceanic plate descends into the
asthenosphere and the materials of the oceanic plate recycle back into the
asthenosphere. The ocean plate was originally created at a mid-ocean ridge
millions of years before is now recycled back. This process ranges from 150
to 200 million years.
Tectonic Processes at Subduction Zones
Visit the following website
http://library.thinkquest.org/17457/platetectonics/4.php
1. Describe how each of the following features are formed due to
subduction:
a. Earthquakes
b. Oceanic trench
c. Volcano
Volcanism
Volcanic activity at subduction zones are often violent!
1. Read page 106 in your textbook and explain why they are so violent.
2. What are volcanic arcs? Provide four examples of volcanic arcs.