Inside the Earth
There are 4 layers of the Earth: 1. crust 2. mantle 3. outer core
4. inner core.
4. inner core.
Restless Continents
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Continental drift is the hypothesis that states that the continents once formed a single land mass, broke up, and drifted to their present locations.
Continental drift also explains why fossils of the same plant and animal species are found on continents that are on different sides of the Atlantic Ocean.
Continental drift also explains why fossils of the same plant and animal species are found on continents that are on different sides of the Atlantic Ocean.
The Theory of Plate Tectonics
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When the plates move they cause an earthquake to erupt.
Deforming the Earth's Crust
There are 3 different types of faults:
1. Normal Faults (Extensional) - when rocks are pulled apart because of tension, normal faults often form.
2. Reverse Faults (Compressional) - when rocks are pushed together by compression, reverse faults often form.
3. Strike-Slip Faults (Transform) - when opposing forces cause rock to break and move horizontally, strike-skip faults form.
1. Normal Faults (Extensional) - when rocks are pulled apart because of tension, normal faults often form.
2. Reverse Faults (Compressional) - when rocks are pushed together by compression, reverse faults often form.
3. Strike-Slip Faults (Transform) - when opposing forces cause rock to break and move horizontally, strike-skip faults form.
The Drifting Continents
254 million years ago: Pangaea existed when some of the earliest dinosaurs were roaming the Earth. The continent was surrounded by a sea called Panthalassa, which means "all sea."
135 million years ago: Gradually, Pangaea broke into two big pieces. The northern piece is called Laurasia. The southern piece is called Gondwana.
65 million years ago: By the time the dinosaurs became extinct, Laurasia and Gondwana had split into smaller pieces.
135 million years ago: Gradually, Pangaea broke into two big pieces. The northern piece is called Laurasia. The southern piece is called Gondwana.
65 million years ago: By the time the dinosaurs became extinct, Laurasia and Gondwana had split into smaller pieces.