- Slides: 16
Inside the Earth
The Composition of Earth • The Earth is divided into three layers… • The crust, mantle, and the core based on what each one is made up of. • The lightest materials make up the outer layer, the densest materials make up the inner layers.
Composition (What it is made of) • Crust • Mantle • Outer • Core Inner Core
The Crust • Outer layer • 5 -100 km thick • 2 types of crust – Oceanic Composed of basalt (rock) – Continental composed of granite (rock)
Oceanic vs. Continental Crust • Composition: basalt • Composition: (rock) granite (Rock) • 5 -10 km thick • average thickness • Temperature= of 40 km. water temperature • Temperature= air to 870°C temperature to Composed of Basalt 870°C Composed of Granite
Oceanic and Continental Crust
Calculating Density… • Density = Mass / Volume
• Composed of mostly of iron and magnesium • Thickness: 1800 -2900 km thick • State of matter: upper mantle is solid, lower mantle is liquid • Temp =870 -3700°C • Density= more dense than the crust The Mantle
The Mantle… • It is made up mostly of iron and magnesium, which is very dense. The mantle acts like silly putty or laffy taffy. • The density ranges from 3. 4 -4. 4 g/cm 3 • Temperature=870 -3700°C • Lots of Pressure!
The Outer Core • It is composed of liquid iron and nickel, which causes Earth’s magnetic field. • It is 2, 270 km thick • It is a liquid • Temp: Up to 6, 000°C • Density=more dense than the mantle
Inner Core • Composed of iron and nickel • 1216 kilometers thick • Solid (Due to Pressure) • Temperature=6, 0007200°C Hotter than the Sun!! • Density most dense layer of them all
Earth’s Layers • How are the earth’s layers similar to an egg? • Shell=crust • Egg white=mantle • Yolk=core
Do you Remember? • 1. What is the difference between • • continental and oceanic crust? 2. Which layer is the hottest? 3. Arrange Earth’s layers from hottest to coolest. 4. What layer is the least dense? 5. A drilling rig can dig down 6 kilometers. What layer of Earth would you more than likely be in?
Physical Structure of the Earth (5 Layers) • Lithosphere- crust and rigid outer layer of mantle (upper mantle) • Asthenosphere- solid rock that flows slowly (like hot asphalt, apart of mantle) • Mesosphere-The strong, lower part of the mantle. • Outer Core- liquid layer • Inner Core- solid, very dense
Tectonic Plates • Earth’s crust is broken into about 19 pieces • These plates move on top of the asthenosphere