Earthquake

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.

Causes of Earthquakes

Earthquakes are caused by the movement of tectonic plates along faults. The release of accumulated stress along these faults results in seismic waves.

Types of Seismic Waves

There are three main types of seismic waves: P-waves (primary waves), S-waves (secondary waves), and surface waves. P-waves are the fastest and can travel through solids, liquids, and gases. S-waves are slower and can only travel through solids. Surface waves are the slowest and cause the most damage.

Measuring Earthquakes

Earthquakes are measured using instruments called seismographs. The magnitude of an earthquake is determined using the Richter scale, while the intensity of shaking is measured using the Modified Mercalli scale.

Effects of Earthquakes

Earthquakes can cause ground shaking, tsunamis, landslides, and structural damage to buildings and infrastructure. They can also lead to loss of life and economic devastation.

Earthquake Preparedness

It is important to be prepared for earthquakes by having an emergency kit, making a family communication plan, securing heavy items that could fall during shaking, and knowing evacuation routes.

Study Tips

• Understand the causes of earthquakes, including tectonic plate movement and faults.
• Learn about the different types of seismic waves and their properties.
• Be familiar with the measurement of earthquakes using the Richter scale and Modified Mercalli scale.
• Explore the effects of earthquakes on the environment, infrastructure, and human populations.
• Review earthquake preparedness measures and the importance of being ready for an earthquake.

[Earthquake] Related Worksheets and Study Guides:

• EarthquakesScience • Eighth Grade
• EarthquakesScience • Seventh Grade
• Plate TectonicsScience • Sixth Grade
• Rocks, Soil and waterScience • Second Grade