1.2A

Question 1

Describe the 2 types of crust?

Answer 1

Oceanic crust underlines the oceans basins and is composed primarily of Basalt
Continental crust underlines the continents, and is composed primarily of granite.

Question 2

What are the rocks like in the mantle?

Answer 2

Near the top of the mantle near the crust the rocks and cool and brittle whereas rocks in the lower mantle and hot and brisk. Rocks in the upper mantle are brittle enough to break and cause earthquakes. Rocks in the lower mantle flow instead of break when subjected to force.

Question 3

What causes convection currents?

Answer 3

Heat derived from the earth’s core rises within the mantle to drive convection currents, which in turn move the tectonic plates.