Plate Tectonics - Chapter 1.3

Question 1

The theory that Earth’s crust is broken into a number of constantly moving plates is called ___.

Answer 1

plate tectonics

Question 2

The plates move in ___ and ___.

Answer 2

different directions, different speeds

Question 3

There are ___ large plates and several minor plates.

Answer 3

seven

Question 4

When two plates ___, they build up huge pressure. The havier plate is forced ___ into the mantle, where is melts. Since some crust is destryed, this is called a ___ ___.

Answer 4

collide, downwards, destructive boundary.

Question 5

When plates ______, molten magma rises up from the mantle, where it ___ and new crust is ___. As a result, this is called ___ ___.

Answer 5

pull apart, cools, formed, constructive boundary.

Question 6

When large plates move, they let out enormous energy. As a result, a lot of activities take place. What are the activities?

Answer 6

volcanic activity, earthquake activity and moutain activity

Question 7

Why do plates move as they float on top of the mantle?

Answer 7

The hot core heats the magma in the mantle. This sets up convection currents in the mantle. Molten magma moves upwards from the core to the crust. Here is cools and sinks back down towards the core, so that the cycle can start again.

Question 8

What is continental drift?

Answer 8

Contitnental drift was when all the contenints seperated.