Plate Tectonics and Igneous Rocks

Earth is made of layers

The Earth is a puzzle made up of multiple plates.

Convection is the driving force for plate motion.

Moving plates can have devastating consequences. Japan March 11, 2011

Convergent Plate boundaries are sites of earthquakes and volcanic activity.

Divergent Plate boundaries are sources of earthquake and volcanic activity.

Transform Plate boundaries are sources of earthquakes. Juan de Fuca Plate in California

All three boundaries interact with one another.

Types of Plate Boundaries (describe the motion): Convergent- Divergent- Transform- What is the cause for plate motion? What is convection? When two plates collide When two plates move apart or divide When two plates slide past each other Heat from the earth’s core causing convection currents When molten rock heats and rises, and then cools and sinks back down creating a convection cell.

Plate activity can generate rocks. Igneous Rocks are found at or near volcanoes!!

Igneous Rocks Come from Magma. Lava Intrusive Extrusive Magma

The type of rock depends on the rate of cooling.

Intrusive Rocks cool slowly and form large crystals. Granite DioriteGabbro Intrusive rocks form from cooled magma (below the surface). Formation?

Extrusive Rocks cool rapidly and form small crystals. Basalt Rhyolite Pumice/Scoria Obsidian Formation? Extrusive Rocks form from cooled lava (above Earth's surface).

Jig-Saw Activity

Exit Card What is the driving force for plate motion? Where are igneous rocks found? What is the difference between intrusive and extrusive igneous rocks? Give an example of an extrusive and intrusive igneous rocks.