Rocks and Plate Tectonics

Question 1

What are the two types of crust?

Answer 1

Oceanic and Continental

Question 2

Compare thicknesses of the two types of crust.

Answer 2

Oceanic is far thinner: 6-10km compared to 30-70km for continental

Question 3

What are the three types of plate boundaries?

Answer 3

Divergent, convergent, transform/conservative.

Question 4

Compare composition of the two types of crust.

Answer 4

Oceanic is made of denser, more mafic rocks, such as basalt.
Continental is made of less dense, more felsic rocks such as granite.

Question 5

Describe a convergent plate boundary.

Answer 5

One plate (usually oceanic) is typically subducted beneath the other.

Question 6

Describe a divergent plate boundary.

Answer 6

Two plates pulling away from one another, usually oceanic (reason for sea floor spread) but the resulting trench would fill with water on land.

Question 7

Describe a transform/conservative plate boundary.

Answer 7

Two plates moving past each other - usually causes minimal impact on land and rock formation.