Science- Plate Tectonics and Continental Drift

Tectionic plate

The earth’s lithosphere rock that is broken into pieces.

Divergent, Convergent, Transform

What movements can occur at a plate boundary?

Convergent

Where does mountains, trenches, volcanoes, and earthquakes form?

Transform, Divergent, Convergent

Where does an earthquake form?

Divergent

Where does new crust form?

Convection Current

When hot molten magma near the core rises becomes less dense, and then sinks as it cools.

Near the earth’s mantle and things like water or air.

Where do convection currents occur?

Magma rises when it is heated and it sinks when it is coole, which creates convection currents.

Describe the flow of magma in a convection current.

The movemnet of tectonic plates.

What does the direction of a convection current determine?

Subduction

When one tectonic plates moves under another and sinks into the mantle.

Along tectonic boundaries. (EX ring of fire)

Where do most earthquakes/volcanoes occur?

Mid oceanic ridge

and underwater mountain range formed when tectonic plates move apart from eachother which creates a new crust.

mid-ocean ridges during the process of seafloor spreading. When tectonic plates come apart, magma rises from the mantle to create new oceanic crust.

Where is the new crust formed during the process of seafloor spreading?

Alfred Wegener

Who proposed the theory of Continental Drift?

Continetal drift theory

That continents move

Pangea

A giant supercontinent

mountain ranges near continents coasts seem to line up perfectly as if they were once in the same place at the same time.

Evidence from land features

The freshwater Mesosaurus and the swamp dweller Lystrosaurus. Fossil remains have been found in Africa, South America, and Antartica. Scientists do not believe that these animals would have been able to swim these vast distances.

Evidence from fossils

Evidence from climate

An island in the artic ocean contains fossils of tropical plants. This does not mean that the artic was once warm because the poles do not receive enough sunlight to produce tropical weather, rather that the Artic used to be part of a super continent.

Convergent

When two tectonic plates move towards eachother.

Divergent

When two tectonic plates move away from eachother.

Transform

When two tectonic plates slide against eachother