Plate Tectonics Flashcards
(11 cards)
Who proposed the theory of continental drift?
Alfred Wegener
What evidence supports the theory of continental drift?
- That the continents were once joined together in one super continent called Pangaea
- Matching mountain ranges
State the theory of seafloor spreading.
That oceanic crust forms along the mid-ocean ridge system from molten material and spreads out away from it
What evidence is there for seafloor spreading and the technologies used to gather evidence?
- Molten material being under the ocean causing convection and pushing away the seafloor
- Sonar equipped vessels that create maps of the ocean floor
What is the theory of plate tectonics?
That the earth’s lithosphere is divided into a number of plates
What is the evidence for the plate tectonic theory
That the shape of continents would fit together, fossils and rock types have been split but previously matched up
How are the plates thought to move?
The intense heat in the earth’s core that causes molten rock to move in a pattern. The convection cell forms when warm material rises then cools and sinks.
What are the different types of movement that occur at plate boundaries?
3 movements at plate boundaries called faults.
- Transform fault/Sliding Plates- where 2 plates slide past each other
- Reverse fault/Spreading Plates- where one plate is forced upwards, causing mountains
- Normal fault/Colliding plates-where one plate slides under another causing volcanoes
What type of plate interaction is likely to cause volcanoes?
Converging plates (Colliding)
How are earthquakes caused?
When plates lock into position and push against each other the strain gets to big and the plates suddenly move into a new position causing an earthquake
What might cause a tsunami?
An earthquake or powerful volcanic eruption can cause a tsunami due to sudden movement
