GED Practice

GED Science Review: The Structure of Earth

Questions:
Directions: Write the answer to each question.


  1. Which type of evidence would be useful in supporting theories about the cause of earthquakes?
    • Earthquakes in the ocean can cause tsunamis.
    • The strongest earthquakes cause the most damage.
    • Earthquakes tend to mostly occur where tectonic plates meet.
    • Thousands of minor earthquakes occur around the world every year.

      Question 2 through 4 refer to the following information and diagram.
      sea floor spreading is caused by the upward movement of heated molten rock from the mantle through the crust. Where this material comes to the surface, the sea floor (Earth's crust) cracks, forming a ridge. The new material in the ridge pushes the sea floor on either side away from the ridge in each direction.

  2. Which statement provides evidence for the theory of sea floor spreading?
    • Sea floor spreading occurs only in the Pacific Ocean
    • Sea floor spreading occurs only in the Atlantic Ocean
    • The crust farther away from the mid-ocean ridge is older.
    • The crust farther away from the mid-ocean ridge is harder.
  3. According to the information given, what is the cause of sea floor spreading?
    • the aging of the sea floor
    • heat currents in the mantle
    • the drifting of the continents
    • volcanic activity along the coasts
  4. Scientists have calculated that the sea floor in the North Atlantic Ocean is spreading about 3.5 centimeters per year. Which of the following conclusions does this evidence support?
    • The Atlantic sea floor will rise.
    • The Atlantic Ocean will widen.
    • North America will become more narrow.
    • North America will have a higher elevation.

      Questions 5 through 7 refer to the following passage.

      The idea of continental drift was first set forth by German scientist Alfred Wegener in 1915. Wegener suggested that one supercontinent, which he called Pangaea, once existed. He also proposed that Pangaea began to break into smaller continents about 200 million years ago. smaller continents about 200 million years ago. These continents that drifted to their present positions. Wegener cited matching coastlines, fossil evidence, similar rock structures across continents, and evidence related to climate to support his idea.
      Most of Wegener's contemporaries were very critical of his ideas. They thought that the evidence supporting continental drift was weak. More important, Wegener was unable to explain exactly how the continents moved. He proposed two ideas—either the gravity of the moon gave the continents a westward motion or the continents cut through the ocean floor. Both of these ideas were quickly dismissed as impossible.
      For many years, little progress was made to explain how the continents could drift. Then in the 1950s and 1960s advances in technology permitted detailed mapping of the ocean floor. From this mapping came the discovery of a  global ridge system under the oceans. In the early 1960s an American scientist, Harry Hess, proposed that the ocean ridges were above upwelling convection currents in the mantle. floor crust away and eventually back down into slip below other plates. Other evidence has since been found to support the idea of sea floor spreading. For the first time, there was a reasonable explanation for how portions of the crust move.
      By 1968, the ideas of continental drift and sea floor spreading were united into the broader theory of plate tectonics. This theory is so encompassing that it provides a framework to understand most geologic processes.
  5. Explain now evidence was used successfully to support the idea that continents and oceans change over time. Cite multiple pieces of evidence from the passage in your response.
  6. Which of the following is a conclusion rather than a supporting statement?
    • the coastlines of different continents match up.
    • Fossils of the same species are found on different continents.
    • Evidence suggests that millions of years ago, the climate was the same in now-distant areas.
    • The continents originally formed one large land mass and then moved apart.
  7. Which of the following natural phenomena can best be explained by the theory of plate tectonics?
    • the occurrence of earthquakes along plate boundaries
    • the recycling of water from the atmosphere to the land
    • the presence of sediment on large areas of the ocean floor
    • the migration of modern land animals from one place to another

      Questions 8 and 9 refer to the following passage and maps.

      There are several types of evidence to support the idea that the continents have drifted over hundred of millions of years. First, some coastlines seem to match, For example, South America and Africa fit together as if they had once been part of the same land mass. Second, rock types and structures found on one continent seem to continue in another. For example, rock types in eastern Brazil match those found in northwestern Africa. In addition, the Appalachian Mountains in eastern North America seem to continue into Greenland and Northern Europe.
             Third, fossils of the same types of land plants and animals have been found in South America, Africa, Australia, and Antartica. This suggests that at one time these continents may have been connected by land.
      Fourth, there is evidence that ice sheets covered much of Africa, South America, Australia, and India about 220 or 300 million years ago. If these land masses had formed a supercontinent closer to the South Pole, that would account for the colder climate.

  8. If you were to draw a map of the world one hundred million years from now, which of the following would the map probably show?
    • The Atlantic Ocean would be narrower.
    • Earth's surface would be covered by water.
    • Earth's continents would be closer together.
    • South America an Africa would be farther apart.
  9. A fossil dating to 200 million years ago is found along the coast of India. In which two other continents should scientists look for the same fossil?
    _____________
    _____________
Answer:

  1. Earthquakes tend to mostly occur where tectonic plates meet.
  2. The crust farther away from the mid-ocean ridge is older.
  3. heat currents in the mantle
  4. The Atlantic Ocean will widen.
  5. many answers
  6. The continents originally formed one large land mass and then moved apart.
  7. the occurrence of earthquakes along plate boundaries
  8. South America an Africa would be farther apart.
  9. Africa and Antartica






Reference:


Complete Test Preparation for the GED Test 2014 by Steck-Vaughn