1. Volcanoes and Plate Tectonics EQ: Where are Earth’s volcanic regions?

2. Vocabulary Volcano – a weak spot in the Earth’s crust where molten material, or magma, comes to the surface Magma – a molten mixture of rock-forming substances, gases and water from the mantle Lava – magma that has reached the surface EQ: Where are Earth’s volcanic regions?

3. Location of Volcanoes EQ: Where are Earth’s volcanic regions?

4. Location of Volcanoes 600 active volcanoes on land, many more under the sea Form in belts that extend across continents and oceans EQ: Where are Earth’s volcanic regions?

5. Location of Volcanoes Ring of Fire –Major volcanic belt –Formed by the many volcanoes that rim the Pacific Ocean Most volcanoes form –At divergent boundaries, i.e.Mid Ocean Ridge –At Subduction zones –Hot spots EQ: Where are Earth’s volcanic regions?

6. Volcanoes at Diverging Plate Boundaries Form along the mid – ocean ridge which is mostly underwater except in Iceland and the Azores Islands EQ: Where are Earth’s volcanic regions?

7. Volcanoes at Convergent Boundaries Oceanic plate to Oceanic plate As the crust subducts it melts back into magma. This new magma is less dense than the surrounding rock so it seeps upward through cracks in the crust forming volcanoes Island Arc – string of islands The curve of the islands echo the curve of the deep ocean trench Major Island arcs: Japan, New Zealand, Caribbean Islands EQ: Where are Earth’s volcanic regions?

8. Volcanoes at convergent boundaries Continental Plate and Oceanic Plate –Andes Mountains –Volcanoes of the Pacific Northwest in the US EQ: Where are Earth’s volcanic regions?

10. Hot Spot Volcanoes An area where magma from deep in the mantle melts through the crust like a blow torch Found in the middle of plates Hawaiian Islands formed over a hotspot Yellowstone National Park EQ: Where are Earth’s volcanic regions?

11. Hot Spot Volcanoes EQ: Where are Earth’s volcanic regions?

12. Class Work and Homework Fill In –What did I learn –Confused –Say Read section 3-1, Review and Reinforce EQ: Where are Earth’s volcanic regions?