Unit 6 Review

The lithosphere is one of Earth's layers. What makes up the lithosphere?

• the inner and outer cores

• the upper and lower mantle

• the mantle and outer core

• the crust and upper mantle

Which layer of Earth is the least dense?

• crust

• inner core

• outer core

• mantle

Earth's lithosphere is composed primarily of which material?

• gas

• rock

• water

• magma

What is the outermost layer of the Earth?

• mantle

• core

• crust

• mesosphere

Which statement BEST describes the relationship between Earth's mantle and core?

• The mantle lies just below the core

• The mantle and core are made up of hard, solid rock

• The core is denser than the mantle

• Material in the core and mantle combines to form tectonic plates

Which of the following parts of Earth may act like a liquid?

• inner core

• outer core

• cruist

• lithosphere

What happens when two plates of different densities collide?

• The more dense plate fractures

• The plate that is less dense fractures

• The plate that is less dense subducts

• The more dense plate subducts

Paul's fav TV show is Volcano Hunters. Each week, a team of geologists travels to a different volcano to try to film an eruption. Where would the team MOST LIKELY find an active volcano?

• near the North or South Poles

• where Earth's crust is the thickest

• where two tectonic plates meet

• anywhere along the equator

Why is the mantle so important to the movement of Earth's plates?

• Earthquakes occur constantly in the mantle, which causes the plates to move

• The mantle is made up entirely of liquid rock, on which Earth's crustal plates can float

• Heavy metals in the mantle set up strong magnetic fields that attract and repel Earth's plates

• Temperature differences in the mantle set up convection currents that help to drive the movement of Earth's plates

Which of the following describes the inner core of Earth?

• It is loose, primarily composed of silica particles, is under the least amount of pressure, and is between 70 and 200 kilometers thick.

• It is dense, composed primarily of solid iron, is under the most pressure with the highest temperatures, and is 1250 kilometers thick.

• It is solid, made up of magnesium and iron, has the lowest temperatures of any layer, and is 2900 kilometers thick.

• It is made up of mainly of silicon and aluminum, has moderate temperatures, and is only 200 kilometers thick.