Day 1

Earth’s Structure Earth is composed of four layers: Crust (outer layer): Thin and nearly all solid rock. Thickness of about 5-50 miles. Mantle: Thickest layer, about 2,000 miles thick. Outer Core: about 1,400 miles thick- it is all liquid. Inner Core: Solid (due to high pressure). 750 miles thick.

A peach can be used as a model of the earth. Think of a Peach… A peach can be used as a model of the earth. The skin= the crust. The flesh= the mantle. The pit= core.

Proposed the Theory of “continental drift” in 1912 Alfred Wegener Proposed the Theory of “continental drift” in 1912 Alfred Wegener was curious. He looked at the shapes of continents and the locations of fossils to understand how continents were once connected. When they are connected, they form a supercontinent. Alfred Wegener named this large continent “Pangaea.” . Alfred Wegener Over time, Pangaea split apart. Continents moved away from each other as the oceans between them grew wider. He called his theory, or idea, “Continental Drift.”

What is the theory of continental drift? The idea that the continents were once all joined together in one super-continent called Pangaea and slowly moved to their current positions Animated Plate Tectonic Reconstruction

Evidence of Pangaea Continents look like they could be part of a giant jigsaw puzzle. Plant and animal fossils found on the coastlines of different continents. Measurements of movement Rock layer sequences

Pangaea Demo Brainpop

Day 2

What is Plate Tectonics? The Earth's thin outer shell is broken into big pieces called tectonic plates. Plates are slabs of Earth’s crust and upper mantle. These plates fit together like a puzzle, but they're not stuck in one place. They are floating on the Earth's mantle (a really thick layer of hot flowing rock).

The Theory of Plate Tectonics The surface of the Earth is composed of about a dozen major rigid, moving crustal plates

What Causes the Plates to Move? Convection- hot magma rises, cool magma sinks (like a lava lamp)

The flow of the mantle causes the plates to move in different directions. Plates move around on top of the mantle like rafts.

When the edges of plates meet, three things can happen: Divergent Boundaries: Group 1 Convergent Boundaries: Group 2 Sliding Boundaries: Group 3

Turn to page 209 in your textbook. In Your Group… Turn to page 209 in your textbook. Find… Characteristics of your boundary. How it moves. What kind of land formation occurs due to your boundary. You will teach the class about your boundary. You will also teach your classmates how your boundary moves, so come up with a movement to show how it moves!

Divergent Boundary: Plates move away from each other. Melted rock rises up between the plates and forms new crust Usually happens in the middle of the ocean floor. Forms volcanoes and new crust

Examples: Mid-Atlantic Ridge Iceland Ridge

Divergent (2nd flap) Forms… Volcanoes and New Crust Example: Mid-Atlantic Ridge

Convergent Boundary Convergent boundary occurs when two plates converge, or move toward each other. They eventually collide. One plate may ride up over the other, while the other plate is pushed under the surface. There are three types of convergent boundaries.

Continental-Continental Boundary Forms Mountains

Examples The Appalachians The Himalayas

Oceanic-Oceanic Boundary Creates trenches (deep valleys) Forms volcanoes Ex) Aleutian Islands (Alaska)

Aleutian Islands, Alaska Examples Mt. Augustine, Alaska Aleutian Islands, Alaska

Oceanic-Continental Boundary Oceanic plate pushes down because it is more dense Creates mountain ranges

Examples… Andes mountains

Plates slide past each other in opposite directions. Sliding Boundaries Plates slide past each other in opposite directions. Forms EARTHQUAKES

Fault line in Tennessee Examples Fault line in Tennessee San Andreas Fault, CA

Animations