AIM: Where are most volcanoes found and how do hot spots form? OBJ: Given notes and activity sheet...

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Transcript of AIM: Where are most volcanoes found and how do hot spots form? OBJ: Given notes and activity sheet...

AIM: Where are most volcanoes found and how do hot spots form?

OBJ: Given notes and activity sheet SWBAT explain where most volcanoes are found and how hot spots form with 70% accuracy

DN: Complete FTE Quiz; Hand-in Finding The Epicenter Lab write-up and FTE scantron.

ACT: Introduction to Ring of Fire, Divergent/Convergent Boundaries, Hot Spots (notes); Watch Hot Spot Animation

Text, read p. 82-85,Work on iPad (eSpark Assignment)

HW: Complete Volcano & Plate Tectonics Act. Sheet; Tectonics Exam, Feb 25

Volcano: is a weak spot in the crust where magma (molten rock) rises to the surface.

Magma: molten rock, gases and water from the mantle.

Lava: when magma reaches the surface.

Ring of Fire: the many volcanoes that rim the pacific Ocean.

Volcanic belts form along the plate boundaries on Earth. Most volcanoes occur along divergent and convergent plate boundaries as well as above intraplate “hotspots.”

Volcano, Magma, Lava

Ring of Fire

Divergent Boundaries:Ocean: volcanoes occur along the mid-ocean ridge where plate boundaries diverge. Here, lava pours out of cracks within the rift valley on the ocean floor.

Continent (land): volcanoes also form along divergent plate boundaries on land along the Great Rift Valley in east Africa.

Convergent Boundaries:

Island-Arc: Volcanoes form where two oceanic plates collide forming an island-arc (ex: Japan, Philippines, Indonesia, Aleutians).

Volcanic Mountains: Volcanoes form where an oceanic plate collides with a continental plate forming a volcanic mountain chain (ex: Andes, Pacific Northwest).

Hotspot: is an area where material from deep within the mantle rises and then melts forming magma.

Hotspot Volcano: forms above a hotspot when magma erupts through the oceanic or continental plate and reaches the surface. Many hotspot volcanoes occur in the middle of plates away from any plate boundary.

Hot spots can form under the ocean.

The Hawaiian Islands formed one by one over millions of years as the Pacific Plate drifted over a hot spot.

Hot spots can also form under the continents.

The geysers of Yellowstone National Park occur above a hot spot under the North American plate.