Earthquakes

Earthquakes

What are earthquakes?

• Earthquakes are caused by plate movement

• The waves that carry energy in a earthquake are call seismic waves

Open Ended

What causes earthquakes?

Multiple Choice

What event happens when there is a sudden, violent shaking of tectonic plates?

• earthquake

• volcano

• thunderstorm

Where do earthquakes happen?

• They happen at plate boundaries or faults

• Most earthquakes occur at convergent or transform boundaries

Open Ended

Where do earthquakes occur?

Multiple Choice

When scientists map the location of earthquakes, where do they find that most earthquakes happen?

• middle of tectonic plates

• in the core of the earth

• only near mountains

• at plate boundaries

How many earthquakes are expected each year?

• Millions of earthquakes happen every year. Most are too weak to be felt.

• The National Earthquake Information Center records about 20,000 a year.

• That's about 55 recorded earthquakes a day!

How many major earthquakes are expected each year?

• That includes 15 earthquakes in the magnitude 7 range and one earthquake magnitude 8.0 or greater.

Multiple Choice

Why aren't all earthquakes recorded?

• happen too far underground

• happen too often

• too weak to be felt

• happen under the mantle

How do earthquakes happen?

• Tectonic plates move and release energy

• The focus is the place where the energy is released

• Epicenter - location on surface directly above the focus

• Energy travels as seismic waves out from the focus

Multiple Choice

What gets released when plates move that causes the ground to shake?

• energy

• light

• soil

Multiple Choice

What type of energy waves do earthquakes produce?

• sound

• heat

• light

• seismic

How are earthquakes studied?

• Seismometer - device that measures intensity of earthquakes

• Intensity is the strength of the shaking motion

• Richter scale measures the magnitude or size of an earthquake

Multiple Choice

Which scale measures the magnitude, or size, of an earthquake?

• Mercalli

• Richter

• weight

• density

Multiple Choice

The strength of the shaking from an earthquake is called it's intensity.

• True

• False