Topic 12 review

The diagram above represents a model of Earth’s surface and internal structure. Letters A, B, C, and D represent four different layers. Some depths below Earth’s surface are shown. Which Earth layer is inferred to be composed of solid nickel and iron?

• A

• B

• C

• D

Oceanic crust is sliding beneath the Aleutian Islands in the North Pacific Ocean, forming the Aleutian Trench at a

• divergent plate boundary between the Pacific Plate and the Juan de Fuca Plate

• divergent plate boundary between the Pacific Plate and the North American Plate

• convergent plate boundary between the Pacific Plate and the Juan de Fuca Plate

• convergent plate boundary between the Pacific Plate and the North American Plate

On the map above, points A through D represent locations on Earth’s surface.Which location is positioned over a mantle hot spot?

• A

• B

• C

• D

The map shows California and a section of the San Andreas Fault. What is the primary geologic process occurring along the San Andreas Fault?

• convergence

• transform movement

• spreading movement

• subduction

Compared to the oceanic crust, the continental crust is usually

• thicker, with a less dense granitic composition

• thicker, with a more dense basaltic composition

• thinner, with a less dense granitic composition

• thinner, with a more dense basaltic composition

Which mantle hot spot is located directly below a mid-ocean ridge plate boundary?

• Yellowstone

• Canary Islands

• Iceland

• Hawaii

The cross section represents the distance and age of ocean-floor bedrock found on both sides of the Mid-Atlantic Ridge.

According to the cross section, every 1 million years, the ocean floor bedrock moves approximately

• 20 km toward the Mid-Atlantic Ridge

• 20 km away from the Mid-Atlantic Ridge

• 40 km toward the Mid-Atlantic Ridge

• 40 km away from the Mid-Atlantic Ridge

The cross section represents the distance and age of ocean-floor bedrock found on both sides of the Mid-Atlantic Ridge.

Which map best represents the pattern of magnetic polarity in the minerals of ocean-floor bedrock on each side of the Mid-Atlantic Ridge?

• 
• 
• 
• 

Which two features are commonly found at divergent plate boundaries?

• wide valleys and deltas

• ocean trenches and subduction zones

• hot spots and island arcs

• mid-ocean ridges and rift valleys

The diagram represents a cut-away view of Earth’s interior and the paths of some of the seismic waves produced by an earthquake that originated below Earth’s surface. Points A, B, and C represent seismic stations on Earth’s surface. Point D represents a location at the boundary between the core and the mantle.

Which process prevented P-waves from arriving at seismic station B?

• reflection

• refraction

• convection

• conduction