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Flashcards in Continental Drift Deck (11)
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1
Q

Who said that the continents were in one landmass and gradually drifted apart?

A

Alfred Wegener

2
Q

What were Wegener’s three main pieces of evidence of continental drift?

A

fossils (Mesosaurus), climate (Greenland), geology (rock layers in S.America and Africa)

3
Q

What is the supercontinent named?

A

Pangaea

4
Q

Why was Wegener’s hypothesis rejected?

A

Because he couldn’t explain HOW the continents moved

5
Q

What is the process where new ocean floor is being made and old floor is destroyed?

A

Sea floor spreading

6
Q

Where is the youngest ocean floor?

A

Closest to the mid ocean ridge

7
Q

Where is the oldest sea floor destroyed?

A

At a deep ocean trench

8
Q

What is the reason Arthur Holmes discovered for the movement of continents?

A

Convection currents

9
Q

Explain a convection current in the mantle.

A

Hot, soft rock in the asthenosphere rises, cools, then sinks, then is heated again. This continues over and over.

10
Q

What are the three main sources of thermal energy transfer in the Earth?

A

Radiation, Conduction, Convection

11
Q

What does the theory of Plate Tectonics state?

A

The Earth’s lithosphere is made up of huge plates that move over the surface of the Earth.