Post on 16-Dec-2015
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:
granite (Rock)• average thickness
of 40 km.• Temperature= air
temperature to 870°C
Composed of Granite
• Composition: basalt (rock)
• 5-10 km thick • Temperature=
water temperature to 870°C
Composed of Basalt
Oceanic and Continental Crust
Calculating Density…
• Density = Mass / Volume
The Mantle• 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…• 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/cm3
• 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=6,000-7200°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