Plate Tectonics Bellwork: Has the Earth always looked like it does today?

Objectives I can identify layers of the Earth. I can identify convergent, divergent, and transform boundaries.

Question What observations can be made that support the idea that the Earth is hot inside?

Earth Layers The earth has four layers, the crust, the mantle, outer core, and inner core Crust-Solid Mantle-Semi-Solid Outer core: Liquid Inner core: Solid

Pair-share questions Compare the Earth’s layers to that of a chicken egg. How are they similar? What do you think happens to pressure as you go inside the Earth? How do you think heat moves inside the Earth?

Plate Tectonics The continents of the earth are part of gigantic plates that move slowly over millions of years Crustal Plates can move apart, slide under each other, and slide against each other These movements produce earthquakes, volcanoes, and form new mountain ranges

Earth’s Crustal Plates

Questions What do you notice about the plates? What do you wonder?

Convection Currents Deep under the earth in the mantle, hotter less dense magma rises to the surface. Cooler magma is forced down to the core where it is heated more, and it rises These movements are called Convection Currents.

Convection Currents

Remember Convection currents move the plates in multiple directions.

Movement of Earth’s Plates

Plate movements Convergence - Two plates push into each other. The place where they meet is the boundary. Land crumples upward and mountains form.

Movement Convergence with Subduction- Two plates meet and the heavier one sinks under the lighter one.

Movement Divergence- Two plates DIVIDE or move away from each other. Magma rises to fill in the Gap.

Movement Transform Boundary- Two plates slide side by side against each other.

Activity Plate movement foldable

Questions for Review How does magma form from the collision of plates? What happens when the plates slide against each other? Predict what will happen when plates diverge, Island formation or mountain building?

Constructed Response The coast of California is due for a major earthquake. Scientist believe that California may fall break away from the rest of the United States. Do you believe that we will eventually be able to predict Earthquakes and why?? Textbooks page 272