Earth History

Read the below article and hypothesize about how it would be possible for the same dinosaur fossils to be found on different continents. on-every-continent.html

1. What evidence supports the continents are in constant motion? 2. How is the energy for moving the large land masses that make up Earth created?

 Plate tectonics: the science of how the large pieces of the crust of Earth move  Continental drift: describes the drifting and sliding motion of the large pieces of Earth  Pangaea: name of a former supercontinent

Scientists think that the Earth was created about 5 billion years ago. At first, the Earth was just a ball of molten rock and gasses. As it began to cool, dense materials like iron sank down into its core. Lighter materials like compounds of oxygen and water rose toward the surface. That's why the Earth is made up of different layers -- as you can see in the cross section on the next slide.

 The Earth is made up of layers. Scientists discovered this through the use of vibrations.  What’s a vibration?

 Hard and rigid, the crust is the outermost layer of the Earth  The crust is also the most narrow of the layers of the Earth. Measuring only an average of 20 miles deep under the continents.

 The continental crust’s surface is where we breathe A lot of rock up to 25 miles deep. The oceanic crust is next door It’s 3-5 miles thick just below the ocean floor. Earth’s surface: 70% H20. Where do you get all that water? Salty sea flow, fresh water’s in the glaciers, ice caps, and snow.  Chorus Throw your hands up for the layers of the earth Throw ‘em up for what’s below the surface Throw your hands up, and let’s discuss The inner core, outer core, mantle, and crust

 Found between The Crust and The Mantle  Made up of The Crust and a little bit of The Upper Mantle  Divided into several constantly (slowly) moving plates of solid rock from which the continents and oceans are formed.

 A section of The Upper Mantle on which The Lithosphere plates float  Made of a hot semiliquid material

 Is divided into two regions. The Upper Mantle, and the Lower Mantle.  This layer is dense, hot and made of hot, semisolid rock.  Found directly below the crust  About 1,800 miles thick.

 Chorus Throw your hands up for the layers of the earth Throw ‘em up for what’s below the surface Throw your hands up, and let’s discuss The inner core, outer core, mantle, and crust  Verse II The mantle layer is the largest of the class. About half of our planet’s mass. The mantle is composed of very hot dense rocks, That move and flow, always on the go, they never lock, Never stop, and they’re responsible for tectonic shift Please believe the Earth’s plates are adrift It’s pretty thick and the heat is awesome 1,600 at the top, 4,000 at the bottom

 The core is divided into two regions.  The Outer Core ▪ The only liquid layer of the Earth ▪ A sea of iron and nickel ▪ 1,800-3,200 miles below the Earth’s surface ▪ 1,400 miles thick  The Inner Core ▪ Extremely Hot solid ball found in the center of the Earth ▪ 3,200-3,925 miles below the Earth’s surface ▪ 750 miles in diameter

 Chorus Throw your hands up for the layers of the earth Throw ‘em up for what’s below the surface Throw your hands up, and let’s discuss The inner core, outer core, mantle, and crust Verse I The layer we’ll discuss first Is the central inner core, in the center of the earth A solid ball buried below the dirt We believe it’s primarily metallic iron You could never take a trip to the inner core, right? The heat will burn you up, 9,000º Fahrenheit 4,000 miles below the Earth’s crust One down three to go y’all. 1,800 miles from the tip top The outer core is hard at work and it don’t stop. It’s busy spinning around the inner core, and listen, This steady movement causes Earth’s magnetism. Ranging from 4 to 9,000 degrees, It contributes 1/5 of the heat flowin’ to you and me. It’s liquid metals that violently flow So let it settle… and when you’re ready let me know. Just…

 Here we go again… Here we go again… This time I want you to listen to the details

 Read the article and Complete the Graphic Organizer.

 Use the rock and fossil evidence to determine how the continents once fit together.

 Read the article about continental drift.  Quickly turn to your neighbor and summarize what you read.  Once you think you have a good summary, record it in your notebook.

 Alfred Wegener proposed the idea of Continental Drift. He believed that all of the continents were once all together and have slowly drifted apart after Pangaea 200 million years ago.

Video Clip

 Boundary The border between two tectonic plates.  Collision Zone The place where a collision between two continental plates crunches and folds the rocks at the boundary, lifting them up and leading to mountain formation.

 Divergent Boundary The boundary that occurs where two plates are moving apart from each other.

 Convergent Boundary The boundary that occurs where two plates are pushing toward each other.

 Transform Boundary The boundary that occurs where two plates slide past each other.

 Fault A crack or fracture in Earth's crust where two tectonic plates grind past each other in a horizontal direction.  Rift A dropped zone where two tectonic plates are pulling apart.

Sliding PlateDivergent Boundary Convergent BoundaryTransform Boundary

 DO NOT EAT THE COOKIE!  Sliding Plate Over Asthenosphere ▪ Use your cookie to demonstrate what this looks like.

 DO NOT EAT THE COOKIE!  Divergent Plate Boundary ▪ Use your cookie to demonstrate what this looks like.

 DO NOT EAT THE COOKIE!  Convergent Plate Boundary ▪ Use your cookie to demonstrate what this looks like.

 DO NOT EAT THE COOKIE!  Transform Plate Boundary ▪ Use your cookie to demonstrate what this looks like.

 EAT THE COOKIE!  Numnumnumnum…  And draw what the different boundaries look like in your notebook.

 On the netbooks go to this website: Complete the worksheet as you work your way through the interactive.

 What evidence exists that the continents have drifted around on the globe over the past several million years?  Glacial scratch marks have been found in regions with very warm climates. Coal deposits have been found in areas with very cool climates. How can this be? Use your knowledge of continental drift and plate tectonics to answer this question.

 Timeline Interactive Timeline Interactive