Ch. 9Lesson 2

What causes earthquakes &

volcanoes?

plate

• section of lithosphere

• move b/c of gravity & convection currents

Plates at our planet’s surface move because of the intense heat in the Earth’s core that causes molten rock in the mantle to move. It moves in a pattern called a convection current that forms when warm material rises, cools, and eventually sinks down.As the cooled material sinks down, it is warmed and rises again.

3 kinds of plate

boundaries

converging boundary

spreading(divergent)boundary

sliding (transform)boundary

2 platescollide

plates moveapart

•plates move past each other

•oppositedirections

Plate Boundaries interactive animation

converging plate boundary

Converging plate boundary animation

spreading plate boundary

Atlantic Ocean-

spreading plate

boundary

sliding plate boundary

California-sliding plate boundary

Which plate boundary type caused this? converging, spreading or sliding

converging plate

boundary

Which plate boundary type caused this? converging, spreading or sliding

sliding plate

boundary

Which plate boundary type caused this? converging, spreading or sliding

converging plate

boundary

Which plate boundary type caused this? converging, spreading or sliding

spreading plate

boundary

Plate boundaries edible activity

Bill Nye Song-Earthquake Rumble

earthquakes•destructive force•occur @ faults along plate boundaries

•energy released can cause landslides & tsunamis

fault• crack in Earth’s crust where surrounding rock has moved or shifted

place on Earth’s surface above focus

place where plates start to slip

Earthquakes [00:57]

landslidelandslide

http://urbanlegends.about.com/library/bl_tsunami_picture.htm

large wave caused by earthquake under the ocean

Tsunami Clay Animation

• Although you might not wish to touch lava with a "ten foot pole“, this potentially hazardous activity is all in a day's work for a volcanologist.

• The long pole contains a

special probe that can measure the temperature of the lava.

volcanoes• form near colliding plate boundaries

• constructive process-makes new land

volcanoes• form volcanic islands when reaches surface of water in ocean