Chapter 8 Assessment

Front

What is the boundary between the crust and the mantle called?

Back

Mohorovicic Discontinuity (Moho)

Front

What instrument records seismic waves?

Back

Seismograph

Front

What is the term for the layer of the Earth located just below the lithosphere?

Back

Asthenosphere

Front

What are seismic body waves that are the first to reach an observer called?

Back

P wave

Front

Why is there a shadow zone for P waves between approximately 105 and 140 degrees from the focus of an earthquake?

Back

P waves are refracted at the boundary between the mantle and core.

Front

What are the two main types of seismic waves?

Back

Body waves and surface waves.

Front

What is the difference between P waves and S waves?

Back

P waves are compressional waves that can travel through solids, liquids, and gases, while S waves are shear waves that can only travel through solids.

Front

What is the term for the area on the Earth's surface directly above the focus of an earthquake?

Back

Epicenter

Front

What is the scale used to measure the magnitude of an earthquake?

Back

Richter scale.

Front

What is the term for the point within the Earth where an earthquake originates?

Back

Focus (or Hypocenter)