Geology Chapter 12 MG

Which of the following layers consist of mostly solid material?

Asthenosphere, lithosphere, mantle, inner core.

Which of the following layers contains mostly molten or liquid rock?

Outer core

Why does a shadow zone occur for P-waves?

P-waves refract as they go through the outer core.

Which of the following best describes the trend in the speed of seismic waves as they travel toward the center of the earth?

Speeds both increase and decrease as a seismic wave moves toward the center of the earth.

Which of the following describes the trend of the Earth's temperature (based on the geotherm) moving toward the center of the Earth?

Temperature increases with increasing depth but at different rates.

Which of the following describes the curved path of seismic waves through the mantle?

Waves are concave up because rock density increases with depth.

How do waves refract in rocks?

Waves refract toward the boundary when moving from less to more dense material. Waves refract away from the boundary when moving from ore to less dense material.

Which of the following behaviors of seismic waves help scientists determine the location of layers in the Earth?

Waves stopping (truncating), refracting (bending), reflecting (bouncing).

What does the iron melting curve tell us about the state of rocks in the Earth?

When the iron melting curve is to the left of the geotherm, rocks are molten. When the iron melting curve is to the right of the geotherm, rocks are solid.

Approximately how fast do S-waves travel through the outer core?

0km/s - S-waves do not travel through the outer core.

Approximately how fast do P-waves travel through the mantle.

13 km/s

Which layer of the Earth makes up more than 82% of the volume of the planet?

Mantle

The _____ is a seismic boundary between the crust and the mantle where there is a dramatic increase in seismic wave velocity.

Moho Boundary

Which of the following describes the relationship between the geotherm and the iron melting curve?

Most rocks are cooler than the melting temperature of iron.

Which of the following statements describes the relationship between the strengths or rocks and how close the temperature is to the melting point of iron?

Rocks that are warm, or close to the melting point of iron, are weak. Rocks that are cold, or further away from the melting point of iron, are strong.

Which of the following statements accurately describes P and S-waves.

S-waves do not travel through the outer core whereas P-waves do.