1. Volcanoes and Plate Tectonics
Mrs. Crabtree

2. Volcano
A weak spot in the crust where molten material or, MAGMA, comes to the surface.
Magma
Is a molten mixture of rock-forming substances, gases, and water from the mantle
When magma reaches the surface it is called LAVA
Recap layers of Earth

3. Lava Cooling Lava cools and forms rock
The is a ______________ force because it adds new rock to existing land and can form new islands.
This type of rock is called igneous rock.

4. Volcano Facts Approximately 600 active volcanoes
Occur above land, but many more occur under the ocean.
Ring of Fire is the area of very active volcanoes in the Pacific Ocean.

5. Most volcanoes are formed at diverging plates.
Volcanoes, like earthquakes, occur most commonly along plate boundaries.
Most volcanoes are formed at diverging plates.
Diverging plate-Where two plates are moving ___________ from each other.
When plates ________ _______ magma can get through the cracks.
Some volcanoes are formed at converging plates
Converging plate- where two plates are being ___________ __________.
There are exceptions called hot spots where there is not a boundary, but a volcano.

6. Converging Boundaries
Occurs where oceanic crust returns to the mantle.
Subduction- process that causes oceanic crust to sink into the deep ocean trench.
Crust then melts to form magma
Eventually rises again back to the surface
Animation

7. When the melted crust erupts as magma volcanoes are formed.
These volcanoes create an island arc
String of islands caused by volcanoes along a deep-ocean trench
Examples: Japan, New Zealand, Caribbean Islands, Indonesia, and Philippines

10. Subduction can also occur where continental crust collides with oceanic crust
Examples: Andes Mountains, Pacific Northwest

13. Assignment Read pages 88-91 Complete Section Review, Questions 1-4
Put all answers in constructed response
Total Points for assignment= 10