Earth Materials & Systems: Earth's Layers

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Across
  1. 4. hot and dense ball of iron at Earth's center kept solid by high pressure.
  2. 5. a boundary between Earth's layers.
Down
  1. 1. hot, liquid layer of nickel and iron around Earth's inner core.
  2. 2. mostly solid layer between Earth's core and its crust; makes up about 84 percent of Earth's mass.
  3. 3. vibrations from a sudden release of energy in the Earth that come from earthquakes, explosions, or large impacts on the ground.
  4. 6. thin, solid shell of rock on Earth's surface that is thicker on land and thinner in the ocean.