Tic Tac Know Crossword

123456789
Across
  1. 5. core / A layer of molten iron and nickel that surrounds the inner core of the Earth
  2. 7. The undersea mountain chain where new ocean floor is produced; a divergent plate boundary
  3. 8. Drift/ Alfred Wegener's hypothesis that the continents were once one huge landmass but have since then drifted apart
Down
  1. 1. /The name of the single landmass that broke apart about 225 million years ago
  2. 2. of Plate Tectonic/ Theory that pieces of the Earth's lithosphere are in motion, driven by convection currents in the mantle
  3. 3. currents / Cause the plates to move; between the lithosphere and the asthenosphere
  4. 4. spreading/ The process by which molten material adds new oceanic crust to the ocean floor
  5. 6. / Thickest layer of the Earth; it consists of two layers - the lithosphere and the asthenosphere
  6. 9. Core / Dense ball of solid material at the center of the Earth