Page 102 - Science Course 2 (Book 2)

The Surface of the Earth Mo10-L4a: What is Earthquake?

Lesson 4

Let’s Begin

In this topic, you will learn the following
lessons:
Mo.10–L4a: What is Earthquake? Earthquakes
Mo.10–L4b: What are Volcanoes? An earthquake is the vibrations caused by the
Mo.10–L4c: What Formed Mountains? rupture and sudden movement of rocks along a
break or a crack in Earth’s crust.

Mo10-L4a What is Earthquake?

KEY CONCEPTS:
1. Where do most earthquakes occur?
2. How are landforms related to plate tectonics?

Vocabulary A-Z The strong shaking of Earth’s surface can damage
both natural features and human-made structures.
Let us learn some vocabulary

earthquake
vibrations caused by the rupture and sudden move-
ment or rocks along a break or crack in Earth’s crust.

Earthquakes occur at faults.

A fault is a crack or a fracture in Earth’s crust along
which movement occurs.

fault Convection currents beneath tectonic plates force
the rocks on either side of the fault to move.
a crack or a fracture in earth’s lithosphere along
which movement occurs.

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