Unit 1- Objective 2

Question 1

What are the 3 types of plate boundaries?

Answer 1

Convergent boundaries: where two plates are colliding.
Divergent boundaries – where two plates are moving apart.
Transform boundaries – where plates slide passed each other.

Question 2

How do convection currents in the mantle create features found on the seafloor?

Answer 2

As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor.

Question 3

Explain the process of seafloor spreading and where the newest rock formed on Earth is found and where old seafloor rock is recycled.

Answer 3

occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor. Eventually, the crust cracks.

Question 4

List 3 pieces of evidence that support the theory of plate tectonics:

Answer 4

(1) the distribution of fossils on different continents, (2) the occurrence of earthquakes, and (3) continental and ocean floor features including mountains, volcanoes, faults, and trenches.