Earthquakes

An earthquake is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. This release of energy occurs when stress on rocks along a fault exceeds the strength of the rock, causing a sudden movement. Earthquakes can range in size from those that are so weak that they cannot be felt to those violent enough to propel objects and people into the air, and wreak total destruction.

Causes of Earthquakes

Earthquakes are caused by the movement of the Earth's tectonic plates. The Earth's outer shell is divided into several tectonic plates that are continuously moving. When these plates rub against each other or collide, it causes a buildup of stress along the faults and when the stress exceeds the strength of the rocks, it leads to an earthquake.

Effects of Earthquakes

Earthquakes can have a range of effects including ground shaking, landslides, tsunamis, and in some cases, even volcanic eruptions. The severity of these effects depends on the magnitude of the earthquake, the depth at which it occurs, and the distance from the epicenter.

Measuring Earthquakes

Earthquakes are measured using instruments called seismographs, which record the vibrations caused by seismic waves. The magnitude of an earthquake is measured using the Richter scale or the moment magnitude scale. The intensity of an earthquake's effects on the Earth's surface is measured using the Modified Mercalli Intensity scale.

Study Guide

1. What causes earthquakes?
2. Explain the effects of earthquakes.
3. How are earthquakes measured?
4. Describe the movement of the Earth's tectonic plates.
5. Discuss the potential hazards associated with earthquakes.

Remember to study the causes, effects, and measurement of earthquakes, as well as the movement of the Earth's tectonic plates and the potential hazards associated with earthquakes.

Good luck with your studies!

[Earthquakes] Related Worksheets and Study Guides:

• EarthquakesScience • Seventh Grade