1. PLATE TECTONICS:

2. Today: Continental Drift Theory-Quick Review Plate Tectonics Video
Reading comprehension worksheet

3. Continental Drift Quick Check –
True or False
Around 225 million years ago, earth was one big land mass called Gondwanaland.
False
Alfred Wegner’s came up with the Tectonic Plate Theory.
Evidence to support Wegner’s theory was the continents fitting together like a jig-saw puzzle.
True
Convective flow in the mantle is responsible for the movement of the plates found on Earth.
Our Earth used to be two supercontinents called Pangaea meaning “all Earth” . 3

4. What’s on your plate?
The Himalayas are growing in height, Iceland is splitting in half, new rock is forming in the middle of the Earth’s ocean and our homes are moving each and every day...
WHY???

5. Questions to ponder?
Looking at the picture below, do you think our Earth always looked like this? Explain

6. Plate Tectonic Theory:
Earth is NOT one big solid rock
Earth is broken down into large and small pieces of rock (like a broken plate)
The lithosphere is broken down into many large rigid slabs of rock (or plates) that move apart and than rejoin.
Movement of these plates ride on the asthenosphere and can create mountains, cause earth quakes, volcanoes, and tsunamis.

7. The surface of the Earth is made up of solid but moving pieces of rock
Lithosphere =
Crust + upper mantle
Asthenosphere =
A partially molten part of the upper mantle
Lithospheric plates =
A rocky solid layer is broken into rigid masses
Theory of Plate tectonics =
Lithospheric plates move around on fluid asthenosphere and interact with others. 7

11. Homework:
Complete reading comprehension worksheet