Across
- 3. process by which one tectonic plate slips beneath another tectonic plate
- 8. huge pieces of Earth's crust that cover its surface and fit together at their edges
- 10. imaginary line on a map that shows points of the same age; formed at the same time.
- 11. study of Earth's magnetic record using data gathered from iron-bearing minerals in rocks that have recorded the orientation of Earth's magnetic filed at the time of their formation.
- 12. ancient landmass made up of all the continents that began to break apart about 200 mya.
- 13. tectonic process associated with convection currents in Earth's mantle that occurs when the weight of an elevated ridge pushes an oceanic plate toward subduction zone.
- 14. long, narrow depression that forms when continental crust begins to separate at a divergent boundary
Down
- 1. devices used to map the ocean floor that detects small changes in the magnetic field.
- 2. place where two of Earth's tectonic plates are moving apart; is associated with volcanism, earthquakes, and high heat flow, and is found primarily on the seafloor.
- 3. tectonic process associated with convection currents in Earth's mantle occurs when the weight of a subduction plate pulls the trailing lithosphere into a subduction zone.
- 4. when Earth's magnetic field changes polarity between normal and reversed.
- 5. Wegner's hypothesis that Earth's continents were joined as a single landmass, called Pangaea, that broke apart about 200mya and slowly moved to their present positions.
- 6. the hypothesis that new ocean crust is formed at mid-ocean ridges and destroyed at deep-sea trenches; occurs in a continuous cycle of magma intrusion and spreading
- 7. place where two tectonic plates slide horizontally past each other; is characterized by long faults and shallow earthquakes
- 9. place where two tectonic plates are moving toward each other; is associated with trenches, island arcs, and folded mountains