1.7 What causes an earthquake?

1. What causes an earthquake?

• The movement of tectonic plates and the release of stress along faults.
• Heavy rainfall causing ground shifts
• The alignment of stars and planets
• Volcanic eruptions releasing gas

What is the mechanism behind an earthquake?

• The mechanism behind an earthquake is the sudden release of energy in the Earth's crust due to tectonic plate movements.
• Earthquakes are caused by volcanic eruptions.
• Earthquakes occur due to the gravitational pull of the moon.
• Earthquakes are the result of human activities like mining.

Where do seismic waves travel during an earthquake?

• Seismic waves only affect the surface of the Earth.
• Seismic waves travel only in the atmosphere.
• Seismic waves are absorbed by ocean water.
• Seismic waves travel through the Earth's layers.

What is the Richter scale used to measure?

• Magnitude of earthquakes
• Speed of tectonic plates
• Temperature of volcanoes
• Depth of oceans

What is the role of a seismograph in measuring earthquakes?

• A seismograph predicts future earthquakes.
• A seismograph measures the temperature of the earth.
• A seismograph measures and records the intensity and duration of earthquakes.
• A seismograph records the sound of earthquakes.

What is the main purpose of early warning systems for earthquakes?

• To predict the exact time of an earthquake.
• To provide entertainment during seismic events.
• To provide timely alerts to minimize damage and enhance safety.
• To increase the magnitude of earthquakes.

What is a tsunami, and how is it related to earthquakes?

• A tsunami is a single large wave caused by volcanic eruptions.
• A tsunami is a type of earthquake that occurs on land.
• A tsunami is a weather phenomenon caused by strong winds.
• A tsunami is a series of waves caused by underwater disturbances, primarily related to earthquakes.

What is the focus of an earthquake?

• The location on the Earth's surface where the earthquake is felt.
• The area where seismic waves are detected first.
• The point where tectonic plates meet.
• The point within the Earth where the earthquake originates.

Earthquakes can only be caused by the movement of tectonic plates.

• False
• True

Seismographs are used to measure the size of an earthquake.

• True

• False