8th Grade-unit 3 test

In the early 1900's, a hypothesis was introduced that proposed a single large landmass broke into smaller landmasses and formed continents, which drifted in their present locations. What is the name of this hypothesis?

• continental shift
• Continental drift
• plate movements
• plate tectonics 

Which of the following statements is evidence for the theory of plate tectonics but does NOT suggest that the continents were once connected?

• the interlocking of present day coastlines,such as Africa and South America
• matching rock layers on separate continents
• similar land features on separated, present-day continents
• thin layer of sediment covering ocean floor, indicating that it was relatively young

The diagram here shows a type of mountain range that can form at divergent plate boundaries. What type of mountains are shown in the diagram? 

• island volcanic arc
• folded mountains
• fault-block mountains
• continental volcanic arc 

The diagram shows the layers of Earth's interior. Which physical layers contain material from the mantle?

• Crust, lithosphere, asthenosphere
• crust, asthenosphere, mesophere
• mesosphere, inner core, outer core
• lithosphere, asthenosphere, mesosphere 

What causes an earthquake to happen?

• Rocks deform slowly as a result of physical stress
• Rocks along a fault move suddenly and release energy
• Large amounts of rock suddenly shift downward when large holes from the underground
• Energy is transferred to rock layers from convection currents in the oceans and the atmosphere 

during the year 2003, the number of earthquakes that occurred was higher than usual. The map shows the locations of some of these earthquakes. Where did the highest concentration of earthquakes occur?

• within the ocean basins
• within the continental landmasses
• along the edges of the Pacific Ocean
• along the edges of the Atlantic Ocean 

The diagram shows a subduction zone. What type of plate boundary is shown in the image, and what type of landform is likely to occur here? 

• divergent; trench
• divergent, island volcanic arc
• convergent, folded mountain
• convergent; continental volcanic arc

Which explanation best summarizes the hypothesis that is shown in the figure? 

• The present continents will gradually move to form a single landmass called Pangaea
• The continents were once a large landmass named Pangaea, which broke apart and gradually drifted to the present-day locations of the continents. 
• The continents were once a large landmass, but the north and south magnetic poles pulled the continents apart toward the poles
• The continents were once a large landmass, but the ocean levels rose, and these oceans separate today's continents

The San Andreas Fault causes many earthquakes every year. The graph shows some of the strongest earthquakes recorded. On the left, it indicates the year. On the bottom it shows the magnitude. What was happening during the time between these earthquakes?  

• Energy built up as stress in the rock due to plate motion
• energy stored in the rock decreased due to elastic rebound
• the fault closed, so there was very little energy to cause an earthquake
• the energy stored in the rock decreases as tectonic plates moved apart

During the year 2003, the number of earthquakes that occurred was higher than usual. The map shows the locations of some of these earthquakes. What is the MOST LIKELY reason that there were no major earthquakes recorded in the interior of the continent of Africa? 

• there are no faults in Africa
• the plate boundary inside Africa is too small to form earthquakes
• the landmass of Africa is too great to be affected by earthquakes
• the entire continent of Africa is located on a single tectonic plate