Earth's Layers
Which Earth layer is the thinnest and least dense?
What is the crust?
Which question would BEST help a scientist compare Earth's inner and outer core?
A. Are both located inside Earth?
B. Are both part of the core?
C. Are they solid or liquid?
D. Are they both very hot?
What is C: Are they solid or liquid?
At which type of plate boundary do two plates move toward one another?
What is a convergent boundary?
Which geologic event can be caused by movement of Earth's tectonic plates?
A. Hurricanes
B. Earthquakes
C. Tides
D. Seasons
What is B. Earthquakes?
What causes the movement of lithospheric plates?
What are convection currents in the mantle?
A scientist discovers a layer that is solid, made mostly of iron, and has the greatest density. Which layer is it?
What is the Inner Core?
Which question would BEST help identify the crust?
A. Is it the hottest layer?
B. Is it made mostly of rock?
C. Is it made of solid iron?
D. Is it the thickest layer?
What is B: Is it made mostly of rock?
At which type of boundary do plates slide past one another?
What is a transform boundary?
Which feature is most closely associated with a divergent boundary?
A. Trench
B. Mid-ocean ridge
C. Mountain range from collision
D. Fault caused by sliding plates
What is B. Mid-ocean ridge?
Which material would rise in a convection current?
A. Hotter, less dense material
B. Cooler, more dense material
C. Cold, less dense material
D. Solid material with the greatest density
What is A. Hotter, less dense material?
A student says, “The deeper we travel into Earth, the temperature and density decrease.” Is the student's statement correct? Explain.
No, the temperature and density increase as we travel into the Earth.
A student is given information about four Earth layers. She wants to determine which layer is the mantle. Which question would give her the BEST evidence?
A. Is it made of iron?
B. Is it liquid?
C. Is it the thickest layer?
D. Is it the least dense?
What is C. Is it the thickest layer?
A scientist observes two plates moving apart. New crust is forming between them. Which boundary is being observed?
What is a divergent boundary?
Why can volcanoes form near a convergent boundary?
A. Plates move apart and create a rift.
B. Plates slide past one another.
C. One plate can subduct beneath another and contribute to melting.
D. The mantle stops moving.
What is C. One plate can subduct beneath another and contribute to melting?
Which statement BEST describes convection currents?
A. Hot material sinks while cool material rises.
B. Hot, less dense material rises while cool, more dense material sinks.
C. All mantle material moves upward.
D. Convection currents only occur at the crust.
What is B. Hot, less dense material rises while cool, more dense material sinks?
Scientists compare two layers. Layer A is liquid and made mostly of nickel and iron. Layer B is solid and made mostly of iron. Which layers are they?
What are the Outer Core and Inner Core?
Mrs. Stout asks you to compare the layers of the Earth using a chart that does not label the layer names. What would you expect to see in the row describing the crust?
A. It is the thickest layer.
B. It is made entirely of nickel and iron.
C. It is the coolest layer.
D. Seismographs showing this layer is entirely liquid.
What is C: It is the coolest layer?
A boundary has the following characteristics:
What type of boundary is this?
What is a convergent boundary?
A student observes a long underwater mountain range where new crust is being formed.
Which process is most likely occurring?
A. Subduction
B. Sea-floor spreading
C. Continental collision
D. Transform motion
What is B. Sea-floor spreading?
A student claims that the mantle cannot affect plate movement because the mantle is solid.
Is the student correct? Explain.
No. Although the mantle is solid, it is able to move. Temperature differences cause convection currents that help drive plate movement.
A mystery layer is the thickest layer of Earth. It is solid but able to move and is made of magnesium and other metals. Identify the layer.
What is the Mantle?
A scientist wants to determine which of two unknown layers is closer to Earth's center. Which characteristic would provide the BEST evidence?
A. Thickness
B. Density
C. Type of rock
D. Whether it contains metals
What is B. Density?
Scientists observe a boundary where plates move horizontally past one another. No crust is created or destroyed, but earthquakes occur frequently.
Explain why earthquakes occur at this boundary?
The plates grind/slide past each other, building up stress that is suddenly released as earthquakes.
Earth's crust is continually being created at divergent boundaries. Yet Earth is not continually getting larger.
Which explanation BEST accounts for this?
A. The crust disappears when temperatures decrease.
B. Transform boundaries destroy the crust.
C. Crust is destroyed at some convergent boundaries as new crust forms at divergent boundaries.
D. The mantle absorbs all newly formed crust.
What is C. Crust is destroyed at some convergent boundaries as new crust forms at divergent boundaries?
Put these events in the correct order to explain how convection currents can contribute to plate movement:
A. Cooler, denser material sinks.
B. Plates move.
C. Hotter, less dense material rises.
D. Temperature differences create convection currents.
D → C → A → B