I. Section 1 Volcanoes and Plate Tectonics
A. Volcanoes and Plate Boundaries Volcano- a weak spot in the crust where magma comes to the surface Magma- molten mixture of rock forming substances, gases and water from the mantle Lava-when magma reaches the surface Ring of Fire- many volcanoes in the Pacific Ocean
5. Volcanic belts form around the boundaires of Earth’s plates. 6 5. Volcanic belts form around the boundaires of Earth’s plates. 6. Diverging- pull apart where mid ocean ridge is, form a rift valley 7. Converging- Where oceanic plates return to the mantle, deep ocean trench 8. Island arc-less dense magma rises to the surface and breaks through
B. Hot Spot Volcanoes Hot spot- where magma rises and forms a volcano Some in the middle of plates, others near boundaries Hawaii, Yellowstone