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The Geosphere Lesson 03:Mechanisms of Movement

Graphic Organizer:Write what you know about Continental Drift & Plate Tectonics

Continental Drift Plate Tectonics

Lesson Objectives:

• Describe evidence for the theories that explain landmass movement and changes

• Compare and contrast the theories of continental drift and plate tectonics

• Describe the three types of plate boundaries and their actions

Evidence of Continental Drift

Mountain Ranges

Fossils

Glacial Movement

Evidence of Plate Tectonics

Apparent positions of the north magnetic pole over the last 500 million years.Ca=Cambrian, S=Silurian, D=Devonian, C=Carboniferous, Tr=Triassic, J=Jurassic, K=Cretaceous, E=Eocene.

Current magnetic poles

Magnetism

Earth’s Plates & Ring of FireAge of Earth’s Crust

Mechanisms of Movement

Convection

Boundaries:TransformDivergentConvergent

Major Tectonic Plates

Plate Boundaries

Show what you know! Title: Tectonic Egg Lab

Introduction:The movement of Earth’s plates is explained by the theory of plate tectonics. The theory has been around for quite some time, but as you will discover in your exploration, it was ignored because the mechanism by which this phenomenon occurred could not be explained.

So, what is plate tectonics, you ask? In a nutshell, the theory states that all the continents and Earth’s crust “float” on a flowing, moving mantle. This movement has broken the crust of Earth into several major plates, or sections, and several minor sections. The movement of these large sections of the crust results in events like mountain building and earthquakes.

In this lab, you will investigate a model that resembles the movement of Earth's plates. When you are finished, you will write a laboratory report of your results.

Tectonic Egg LabObjective:

Create a model of Earth, using an egg, so that the movement of lithospheric and asthenosphere material can be observed.

Problem: What happens to the asthenosphere as lithospheric plates move at the three types of plate boundaries?

Hypothesis:

Materials (for hands on lab): – water– pan– raw egg– cracking device such as a teaspoon– paper towels or newspaper

Tectonic Egg LabProcedure:

• With the assistance of an adult, boil an egg until all parts are cooked (about 10 minutes). Pour the water off and allow the egg to cool. If the egg is not cool to the touch before beginning, you could suffer a burn. You can put the egg in cold water to cool it more quickly.

• Once the egg is cool, use a cracking device, such as a teaspoon, to lightly tap the shell in several places so there are several large cracks in the shell. Do not make too many cracks. There should be several large pieces of eggshell.

• Place the egg on a layer of paper towels or newspapers. • Try to move the pieces of the cracked egg shell around on the surface of the egg. (Don't

remove them; just see if they slide around.) There should be slight motion allowed by the membrane holding the shell to the rest of the egg inside.

• Next, find two sections of the egg that are fairly large and on opposite sides of a crack. Use your index fingers and gently pull the two sections away from each other. Observe what happens in the area of the crack between the pieces. Record your observations.

• Stay in the same area of the egg and push the two pieces toward each other. Observe what happens in the area of the crack. Record your observations.

• Stay in the same area of the egg and try to slide one section of the shell up or away from you and pull the other down or toward you. Observe what happens in the area of the crack. Record your observations.

Data and Observations: 1. Did the experiment support your hypothesis? Using the data from your

experiment, describe why you believe your hypothesis was either proved or disproved.

2. If the egg is a model of Earth, what does each part of the egg represent?

3. When you moved parts of the eggshell,a) What occurred in the area of the crack when the two pieces were pulled or

pushed apart?b) What occurred in the area of the crack when the two pieces were pushed

toward each other (together)?c) What occurred in the area of the crack when the pieces were pushed so that

they slid in opposite directions past each other?

Tectonic Egg Lab

Egg/Earth Counterparts

Portion of the Egg Part of the Earth It Represents

Whole egg

Eggshell

Cracked pieces of the eggshell

Egg white

Egg yolk

Tectonic Egg Lab

Analysis and Conclusion:

In your own words, write an analysis of the differences between the types of tectonic plates and the resulting observations in the asthenosphere. Be sure to include terminology from the lesson and direct references to your data.